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Seasonal morphology and histology of the androgenic gland of the crayfish, Orconectes nais
GENEHL
AX,)
Seasonal
(‘OMP~R.I’l’lVI~:
I’:SD:)(‘IlISOLOGY
15,
143-157
(1970)
Morphology and Histology of the Androgenic Gland of the Crayfish, Orconectes nais
bI:rle OrcotLec6es TK& were hatchrd in the spring and completed an unknown number of Form II growth molts during the summer. The population molt from the sexu:llly inactive Form II to the sexually active Form I occurred in late -August and c:nly- Scptcmber. The populntion molt from Form I hack to Form II occurred in the sl,ring. Some males, smaller than the norm for the population in late summer. remained in Form II during thrir first year and completed the first molt’ cycle in their sccontl year. Crayfish older than 1 year represented a small percentage of the population ; lrowcvcr. the limitctl datn establish that, some males complete more than OIIC molt cycle am1 more than one period of reproductive act,ivity. The antlrogenie gland of the youngest crayfish examined consisted of a small nmnl)cr of small ~11s with dcnsc. homogrncous cytoplasm and closely associated \vit 11 the, \‘:r;r‘ tlefcrcns ; no foci of ecllular degencrat,ion were observed. The androgenic ~l;md incrcanctl greatly in sizr tlurin, n the summer. The gland proliferated as a shcctlike% :ur:mgcmcnt, of mnsscs of cells and pnrnllrl and annstomosing cords; however. the 41s cnlargctl only slight,l~- and the c~ytol)larm rcmaincd homogrnt~ous. C)cc~asion:d foci of cellular dcgcncrat ion wcrc observed and invol\.ecl from as few as two cells to :I niu~11 Ixrgcr numhcr. Thr androgcnic~ gland at,t:rined its maximum size a wrck or t\vo prior to the t)opul:rt ion molt from Form II to Form I. The gland changed from tlrc Ilrc\.iott* shcrtlikc arrangement to onr of rntwined cords. Further, the ~11s were anti eontaincd vesicular cytoplasm ; areas of cellular deI:ugfl~ hyp~~rtrophictf gcncmtion were hot h romnmn nn(l cxt endive. ‘I’(3ticul:u m:rturation ;ui~l ~;l)c’rnl:Llopc,nr~ia occurred fxrly in the summci-, an(l g~~rrcr:dl~spermatogcnc& wad ahsrnt in Bngusl,. although sl~erm wcrc ret,ained in the V:W tlcfcren~ during the winter. Thus, tcst,iculnr activity largely preceded the t)rolifcr:ttion of the nndrogrnic gland and occur& whrn the androgenic gland conl:rinc~cl t)rirn:nily tlrc small eelI :mtl only oc~c:lsionnl arcas of cellular degeneration. The, nlolt from Form 71 to l’orni I nml ttlci suhscclucmt tlcriotl of rrproducti\-c activity W’K nssociatcd Tvith an androgcnic gland of maximum size that contained l~rim:uily 11?I)c,rtrol)hic~ri eclls wilh vesicular cytoplasm and numerous, cxtcnsil-c arc:rs of cellular dcgscncration. Tlrc ohsemations intlicatc that, tlrc ;mdrogenic~ gland posscsscs sufficient a,rtivit> prior to and during its tlroliferation to stimulate trsticular maturation and spcrmatogcnc>& l,rtt insufficient activity to stimulate the differentiation of t,he Form I gonopod ; thcb differentiation of the sesu;dly ;nt,ivc gonol)od and the rcpro(lu(,tivc’ rrctivity that, iollows the molt from Form II to Form I may occur in response to :m in(,rc:rsc in thr activity of the androgenic gland. Although some activity must IW :rssrlmcd for ills androgmir gland prior to and tlrtring the ljroliferation of the, gl:rntl. the ~11s rcq,onsihle for thcs activity remain unknown. If the foci of cellular hgpcrtrolh? and dcgrncration rcq)rrscnt holocrinc secretion. the small arcas of dcgenerat ion or~casionally ohscrvrd during the proliferation of the androgenic gland ~ot11d account, for the low level of activity suggested to be responsible for testicular tmttmation and sl)crmatogcncsiz ; the increase in the number of hypert.rophied cells im(l t 111’ more numerous and cxtmsivr arras of cellular dcpcnerat,ion could account 14:;
rq,ortcd the androgenic gland to bc of a holocrine t,ype, hut King (1964, 1965a, 19651s) did not find evidence to support, holocrine secretion. The purposes of the present study were to describe the androgenic gland of the (brayfish, Orconectes nais, and to determine ii thcx androgenic gland undergoes seasonal lnorphological and histological changes indicative of activity and related to reI)roductivc activit,y and the molt cycles of tllc animal. The molt and reproductive c.yclcs of crayfish species have lmw deicril-)cld by Steele (1902)) Ortman (1906), Van Deventcr (1937)) Tack (1941)) and Snutlamore ( 1948’). Jlalcs of the auhfamily ( ‘ambarinac cxhihit an cxternwl sexual which divides thr male climorphism I)opulation into sexually active (Form I) and sexually inactive (Form II) animals. .\Ial~ in their first summer of growth ~~ntlergo a sclricasof Form II molts. Reginlling with the first, molt to Form I, malts tnolt altcrnatcly between Form I and Form 1I during seasonal molt periods. Crayfish it) Form II are the functional cquivalcnt of protandric hcmaphrodites in the interrex .stattx that, posso~scs a testis hut, no copuiatorp organs. Thus:, if the androgcnic gland I*ontrols male sexual differentiat,ion in the c~rayfish, one might expert a c~orrclation l)et,wecn androgenic gland morphology and t tl(h morphology of the secondary SC’schar;ictcbrx and the testis. MATFXIAW
AND
METHODS
d ~~ZmaIs. Male cravfish were colleckd by srlinc from ponds locatcvl in Boone County. Missouri. (‘myfish ww prrs~~~l from mid-June. 1965. i.hrough Drccml)er. 1966. The numbrr of animals r~ollvctcd varied with thrir availability. Ten to 20 malts wcrc llrcsfvod per collection date when Ijos*ihlc ; howrvrr. midwintrr collections wcrc (sornl)oscsd of only t,wo or thrcr animals prr rolIvction datr. T>uring the following l”riods c-rayfish we’re prrscrvrd from a stock which was n~:tint.:rinrd in the laboratory for periotls ranging iron1 2 we&s to 4 months: Octobrxr, 1965, through I~‘&nu~rq’, 1966 ; Junr through mid-August,. 1966 : Novfvlbcr through December. 1966. Laborator> :mimals w<‘rc krpt, at, room tmmprmturr in running rap watclr and wrrc fed liver once a wrrk. Animals \vvrv st~l~c~lc~~l and prcsr,r\.xl fxm c’:rc,h siz:l (*la88
I,rf~sf~rrl. 111 the scinc or actuarium and 7lol on t,lle basis of their numbers in the population. ‘I% form and ccphalothoras length wrre recorded for and year rl:~sscs wf’r(’ each pwf~rvcd animal, assigned on t,hf) b:r& of ;iizr. animal wit* op~nr~l ‘I’issue I’reprtrfim. Thv ventrally to assure rapid fixation of thrl rqxoduvtive organs and androgenk glands. E‘ollowiue fixation in neutral formalin. t hc cxr:q~:icv dorn:d to the fourth and fifth prripods was rcmovcttl and the \-as dcfrrrns rut, to l)rcTvcnt to:ikp. ‘1‘11(’ fourth and fifth legs WV(W disarticulutc~d a~ :L r~nil and the coxapoditrs staincvl with 0.5’4 mvt tryknc, blue to bring out muscular d(ltail anti to ln:k(~ the androgcnic gland xisibl~. The va:: dofvrvns (in the fifth lrg) was cut, :mtc>rior to thv &inning of the cnlargetl mus(&ir portion. and t11(! cvnt ire, post&or ~-as dclfvrvns ivas rvmo\-rvl. ‘1’11~ :m(lrogrnic gland is tlificult to r(vlo\-fx cvnll)l<>ttily IN’cause: of its diffusr nature: l)ortions 0C thv glxlcl frequently :II’(~ not. firmly :Iltac~~lf~tl to 111v 1 :I* dtxfcrcyx+ anti cstcnd a c~on*iclc~tal)lr tlistanc~c, into thrl surrounding ronncctivr Iissue. Tlrv testis \V:S rt~movcd. and one lobt~ was processed histologicall> with thfl caorreq,onding :mdrogSc~nic~ gland. T(~mpor:lry whole mounts of vnsa drfcrcxtk :nl(l androgc~nic glands were staincvl 17ith 0.5’;; mPt h?lent’ I)lu~~. Prrmanmt, whole mounts \v(‘rv rlvIlydratrsd in alcohol ant1 Stain& with I.yncll’s precipitated borascarminc~ (Galigher :md lioz!ot’f. 1964). Rcrial par&n sect ions of andl,og(>nic* glands and thv vorrcst)oncling t(vtPd wart’ rut at. 10 ,U :mtl stained with Harris hrmatosplin and rosin. .\letltoc/ of S//rt/y. Two svrirxs of obsc,rv:rtions wcrc mad(~ on t hv nndropc,nic* glands. In tllc, first scrims, tc~mporary whole mounts of entir.c> glands from at least two animals per collection (lattx wvrv r:tifvl m terms of t hvir r.c,lntivcx size and morlhology ; alkolutf~ m(~ikxircnlvnl of androgc~nic~ gland volume x:s not, frasiblc tiuv to the diffuse nature of ttw gland. Thr following rating systvnl was :i~~~)liivl to thr glands:
Tylv II. (Aand volume much grcxatcr than Typo I : lary& portion consists of :L shc~c~tlik~~ arrnngemcnt of masses of cells and paritllc~l or anastomosing cords which extc,nd from t hca V:W dcfcrcns into thr surrounding connctivc tissue. ‘\ small number of entxinc,d cords closely associatrd nith th(l Y:lS dvfrrcns also arr prcsrnt (Figs, 51, and 5c). Tyler III. Gland consists primarily of mntwinctl cords although gland ~olumc may be equal to Typrs II. Cords are present along the vas defrrens and arc associated with a large branching ncrvc some distance from thr vas dcferens; small islands
lctt:. deferens
1. Diagram of the male ivd), attdrogettit~ gland
reprodttciive Cage, and
systenl of 0. nuis getlila papilla igp I.
Aowittg
the
lot*:ttiott
(,f ttt(i
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25 :t!td 35 mm cel~lialot.ltorax wrc itt tltcir first yrar hut had hatched unusuall;v wrly in the spring. Animals greater than 41 mm celthalothorax at any season wrc assigrtc~~l to tltc second year class, although it ib ltrol~al~lc t#hat, some of tltcw animals wvro in at lcast~ their third year of lift. III t,ltis possible third year ~~1:~s~wart’ w\w:tl animals grvilter than 45 mm ccI~lialotliot~~tx at the cttcl of the summer growing ,wiwott tltat orcr-wititc,retl in the lal~ot~a~ot~y.
Forty-out millimeter celA~alothorax was t Itv Gimatcd maximum size for animal> ifI their first year of life based on tlte tlktrihution of size classes during the sampling period (which included two summcm) of the (Fig. 21 and on observations ttumh(w of animals iii each size class in ltottds which were drained yearly. Clearly, iuxtty animals did not attain tltis nii~ximuiii size, nor did all animal:: molt to Form II hy tltcn (911 of tltc first growing season. Xtiitnal~ Iwtn-cvti 25 and 35 mm ccl~ltalot,lior:~x in intrrprc~tc~~l to 1~ .I 1111(’ ant1 .July wcrc >(wtt(l ywr crayfixli in their first molt, I*\-clc wlticlt had not reached population t1orms at tlw end of the prwious growing ..(‘:t~ou. Howcvcr, it is possible that. at least ..ottt(s of tlw .Junc and .July animals hetwccn
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t~iorl~liology :kttd histology of the ntidrogc~rtit gland of t’lic crayfish arc’ presented itt Figs. 2, 3, and 4. The acasonal morphology artcl ltistology of tlic antlrogenic glantl :ut(l tlit, wasonal dcvcloltment of the tw:tis it1 crityfish in their first year map Jw sutttttt:trizo(l
July
I
I Aug
Sepr
I I Ott NO” Dee Month
I
I Jan
I Feb
, Mar
J Apri I
2. Relationship between size, form, and time of year in 0. nais. Each point indicates in the population. Solid circles represent Form II; open circles represent, Form I.
a size and form
Type II
TypeI,;y
:;
he
July Aug. Sept. Ott
:,
,
,O,-:
,
NW Dee Jon. Feb. Mar. Apr. May
E’I~;. :<. Relationship between androgenic glntrd morphology, form, alld time of year in 0. nrris. Ciwles represent, animals est.imsted to be iti t heil first, year; squares represent animals estimated If> be older than 1 year Solid symbols represent. animals in Form IT, fq~er~ symbols rrprrsellt :Itlimnlr ill Pfm~
1.
TYPOD
P Type A
June July Aug Sepl Or1 NW Der Jon
Feb Mar Apr
thy
YIC;. 3. Relationship between androgenic gland histology, form, alrd time of year in 0. nnzk. Symbol< as in Icig. 3. I>irec%ion c,f the arrow- indicates thr minor
f:ell
type
presellt.
149
FIG. 5. Whole mounts of the vas deferens and associated androgenic gland (arrows) in 0. nois. X7.4. (aj Minimal gland (Type I) from a June animal in Form II; (b) maximally proliferated gland (Type II) from an August animal in Form II; (c) initial development of entwined cords (Type III) from an August animal in Form II; (d) maximal developmentj of entwined cords (Type IV) from a Sept,ember animal in Form I.
1”1n. 7. Sectiolw of the alldrogellic gland in 0. nuis. (a) IJocxl area of degeneration loc:ited 10 I* from t.he area shown in Fig. 6:~. X525; (b) Xassive degeneratiotl of the gland (Type E) from a .\lay animal in Form 1. The darker cells ilr the right one-half of t,he photograph represent the invasion of the gland by basophils and eosinophils. X263.
tht> tcet,cs were filled with
sperm in late
.?\ugust.
‘1’1~ population molt from Form II to ForIn I took plncr in late August and early Scljt cwhcr in first year animals of at least
25 mm cephalot.horax. During this lwriod, the androgcnic ghml incrcaxd only slightly in total size, but the sheetlike area of the androgcnic gland decreased in Yolumc and the awa of cntwinotl cord:: in-
152
CAHPESTEH
creased in volutnc. By late September, the sheetlike area was reduced to islands or had disappeared entirely, and the androgenic gland of animals in Forrn I showed maxirnum devclol~mcnt of entwined cords (Typca III, Fig. !&I). The cords began posterior to t,he constriction on the convex surface of the vas deferens and continued posterior15 rotating 180” until they reached the bascx of the large nerve described above. Cords or islands of cells frequently were founcl also along several nerve branches sorn(’ distance from the vas drferena or (‘\-en oxtended along or between small skeletal tnuscle fibers; this portion of the gland often was lost in dissection or processing. Importantly. not all of the crayfiqh followed the populat,ion norm for molting. Tltcs majority of crayfish under 28 mm remainctl in Forrn IT throughout thr yrar. In addit’ion. four anirnals were exarninctl that wcrc at least 34 mm cephalothorax but were still in Form II in early Ott,ober. Of thcasc. two showed androgenic glands in the proliferative stage (Type II), and one showed tnaximally entwined cords (Types III) ; the remaining anirnal had a rcdurchcl androgenic gland (Type IV). In addition to the gross morphological changes of the androgenic gland, the histology also changed during the period which began at least 2 weeks prior t,o the first rnolt to Forrn 1. In two August animal:: in Form II and in almost all September attimals in Forrn I the dominant, cell type was Type C. These cells showed a definite ittcrease in cytoplasmic volume and a chattgr itt cytoplasmic character frotn relatively dense to mot-cl vesicular (Fig. 6b). Typta B rclls made up the remainder of the glattcl. Foci of dcgencration such as those drscrihcd above were common in the androgrnic glands of Scptcrnbcr animals itr Form I. Most testes taken frotn Form I animals in late August and early September had tZubulcs filled with mature spc’rnt, but spertnatogencsid essentially had cea9clcl I)\early Sept,ember. The majority of first. year animals caollectcd through the fall, winter, and carI> spring were in Form I (Fig. 2). Tltca attimala largely disappcarc~cl front tltcs opt’tl
AND
I)EHOOH
water as the weather ttrcatuc colder in thr. fall (,November) and wv(‘i’(’ not Itrcs(~u[ again until March; cott~eqttt~tttly much oi the data on winter attim& wt’r(’ tnkc.11 front animals maint,aittr>cl in the laboratory. During the period Oatobcbr through Altt:ii t>lte androgcnic glands of most, animals in Form I retnained as entwined cords (‘l’yl)ta III or Type IV with reduced volutntb) ; sottt(’ returned to thr shectliktb arrartgenit*tt! ( Typr II I Histologically Tyl~ (’ rr~mainc~(l I II(, clominant cell type during t,hc fall! although cells with maximum vcsicbular cytoplasm tTyltc> D, Fig. 6c 1 WIY present iti tltcj gland. Extensive area+ of ~11 degctrerutiotl (Typtb E. Fig. 6di also were present i11 ttlc, glantl of one Sovembrr animal. Thcx itttdrogenie glands of Forttt t (brayfish collocto(l cluritig Decetnbt~r t,hrough Jlnrch w~iy’ characterized by a r&urn to the sntdl (101~~ ~11s of Type B, although Type (’ ~11,s ~vct’(~frc~qucntly presc>tit a5 the minor WI i typo. Arcas of ‘I’ypcl (’ ill+ sltowr~rl t tit, usual irtcidencc of degt~ttcr:~tiott.
Tlrcb ltoltulat~iott tttolt frotrt Form I to Form II began itt Xltril aliti oorttinuecl through the Spring. Form I and II animals 1~s than 41 mm c~cl~li~~lotliorwx iti tltc, pc~rioclApril through ,\lay had sttiall attdrogettic gla~tds (Tyl~ I ;t~~tl l’g~w 11. I ; OII(’ Fort11 II c*rayfish hati :ttt ;Ltt(trogctti(’ gl:tl~rl iii tlici ltrolifcrativc *tage ITypc~ II 1. ‘Q-IN B was the dotninant ~11 tyl)(> in tlttl glan(lh of ;~ttimals in both FOIXI 1 anal Form I I tlurittg Altril :ititl Jlwy. \\.itlt on(’ ~~s-~:‘il)lr~ c~xcc~lttiott. 110 cxccssivc. tleg(~iteratiitn \vi~i t-rotc,d in tlicls(t gIantIs. The tc+tir \v:is not ox:ituiti(~~l cluritig t1ti.GI)~~rioct.
CK.4YFIBH
Ah-DROGENIC
tory and thus were know1 to lue in their second (possibly third) molt cycle and/or year. June and August Form I animals had reduced gland volumes and cells of Typv B, C, or D; no Form I animals were c~ollwted in *July. Second year animals in Form II in early summer had glands in the I)roliferativc phaw (Type II) and containr~d the *mall, dcnw ~11 (Type B). Ko second \-car crayfish wre arailablc during the critical Jwriod l~ctn~~~n late August and (SarIy October. .I11 second year or older animals cxamilled in late Octohcr through Dccemher WT’IY’in Form I. as wcrc t)hc majority of :mimals in the first year cycle (Fig. 2’1. Th(w large crayfish were collected when 11pond was clrained. Most’ of these crayfish hacl reduced androgcnic glands (Type IV 1, :m(l the remainder had glands of Type II or l’ypcl III. Kith two excrptions, all ani~nals cxaminc~cl from October through April in tjot,h Form I and Form II had glands which ww composed of highly vesicular wlln with large areas of dcgcncration I Tylw:: 1) aud E:), and beginning in .Jwlluary almost all glands showecl maxi1~1111dclgencration (Type E) However. it mwt lw notcacl that while degeneration was witl(qwatl in thaw glands, it was never wniplc~t~~; tlww ww always many ~11s I)rt,..c,nt8which appc~arcti normal. (My a few crayfish were examinctl in 11:~~ at the crd of their second or third year. OIIC Form II animal had an androgenie gland of maximum dcvelopmcnt t Tylw III). Examination of a gland from a Ilay animal in Form I and one’ in Form II ~how~l maximum clcgencration (Type rc 1. ~;l)crrilat’ogciiesis did ocwr in the testis of son1~~animals in at least their wco~~d molt (cyclic. Spc~rmatogenic activity was present in t hv t&is tubules of Form II animals in lwth .Junc anal .July. Howcrcr, two Form I ;tninials which wrv examinetl in .Junc (lit1 not dcmonstratv ~pcrmatogenesis. No twtc,s wwc c~xaniinetl for spc,rriiatogcrlic, activity iii August or Srptcn~her. Mwturc qwrni wcrc prcs;cnt in thfs testis of Octolwr anin& in both Form I and Form II. Tlw test is was rcgrc5wtl in gross appearance ill nio,-t Novcnib and Dtwmher animals iii
GLAXIII)
153
Form I. although mature sperm frequently were present in the vas dcfcrens of winto] animals. X0 animals were examinetl for testicular drvclopment from .Januar> through May. No method has been dcwloped to accurately age crayfish or to tletcrminc thv numbci of molt, cycles and assoriatcd periods of reproductive activity completed by an individual crayfish. In the ahscnw of information derived from animals of known age, size is a logical criterion to use. Crwyfish larger than the maximum size attained by the population at, the wtl of the first year, estimatcvl to 1~141 mm cephalothorux for 0. nais, can reasonahly hv assumed to be in at least their second year of life. Tlit~ possibility that a frw individuals eiitr~~ their third year of life is suggested 1)~ thv large dizc of some crayfish in the spring. The majority of crayfish complete the first molt cycle and the assoriatcd pcriotl of reprocluctivc activity in thrir first ywr; howvcr. at least. sonic animals appear to remain in Form II throughout thv first year and complctc the first molt cycle in their sccoud year (SW lwlow) In addition. the data indicate that soiii~~ crayfi.;h cornpletc, more than one molt cycle and mor(1 t81ian one period of reprotluctivc activity. Thv extent to which more thtan one molt cycle and pwiod of wproduc$ivc a&vity occurs in t,lic J~opulation was not iuwetigated and remains 2111 intcrwting and important question, particularly ar it rclatw to androgenic gland coutrol. &low than one molt cycle anal rcproductivc~ period also liavc lwrn reported for Cnmbrrrus ‘oDsc7c1.1~~ (Ortmann, 1906) and 0. (C~nmbnr7~n) pfoping7rus I Van Del-cntc>r, 1937). Ollly 0Ilc molt cyclr and 011~‘ r(‘productive period, generally over a 2-y(aai period, is rcport~ctl for 0. (Pam6nru.s) iv/nzunis (Tack, 1941 1. The androgenic gland of 0. nnis is similar to that of other wptantian dcc*apotl~ with regard both to it.< location and its nlorJ~llology and histology (rf. rwiem i)y Charniaux-Cotton et 01.. 19661, and 110 romrnrnts in addition to the doscriptioii prcsrntrd in tlirb Kwults aplwar wari-antclcl.
CR.ZYFISH
ANDROGENIC
IL to Form I and the subsequent hrecding behavior occur in response to an elevated hormone level. An explanation based on different t,hresholdx of tissues to a hormone and changing le\-cls of the hormone is not without precedent, and is well documented for the thyroid and the control of amphibian tttetatnorphosis (Turner, 1966). In addition, I)cmeusy and Veillet (1958) reported that I)ilat,eral eyestalk extirpation of C. maenas rwults in the sitttultaneous hypertrophy of the androgcnic gland and precocious growth of the reproductive organs. A seasonal and progressive lifting of cyertalk itthit)ition would provide the mcchatGtn for the suggested rise in the secretiott of the androgettic gland hormortv. \\Me it appears clear that some act,ivitp must 1~ assutncd for tltc androgenic gland Iwforcs and during it:: proliferation, the cell typch rwpotisihle for the secretion of the ttortttottc remaitts uttattswercd. CharniauxCotton and her co-worker:: (Charniaux19.54. 1957. 1962; Charniaux(lotton. Cotton et nl.. 1966) have dcscrilwd the following ~11 types itt diffcrcnt areas of t tte crustacean wndrogettic gland : small. ~lctt:‘(~ ~11s without cyt’oplasmic vacuoles, largcjr cells with vesicular cytoplasm, and cell- in various stages of degeneration. Ttt(w authors c~oticlurlcd that the attdrogettic gl:md wcretcs in a ltolocrinc mattn(~r. Itt 0, Tunis ttiv increase in cell size. ttic ch:tngw in cell tttorpliology, and the ultitnat(b degettrrntiott of t,hc cells are consistent, with holorrinc~ scwetiott. Further, fori of clvgc~ticwtiott arc’ always prcwnt and Y:try ira~onall~ iii nutiilwr and area. hltltouglt loc:~lly clegcncratc area8 do not appear to ltav,, :I constant locatiott in the attdrogcnit qlatltt, the degenerate area is oftctt periph(BraI to a mass of dense cells. A rimilar at*r:ittgt~tncnt iii Cnllinectes strpirlris wils intc~t~prctcd tw Tcholakian and Rcirhard 11964) to inriicatc holocrinc secretion. If tltcb local areas of degeneration ohier\.cbtl it) the attdrogcttic gland of 0. rlnis rcq)rcwttt holocrinc wcrctiott, tltc mall ttutnlwr of local areas of cell ltypwtrophy ant I tlt~gcwcration ohserved in the growing ;ut(Irogcttic gland of Form II crayfish could account for the low hormone conrctttration iuggwtctl to lw rc~spottsiblc for twticulnt :lc.ti\,ity : thv itt(wawd titer of hormone
(:T,.iNI)
lpi.5
suggested t’o occur prior to the Form II to Form I molt may be produced by the more extensive and more common areas of cell hypertrophy and degeneration observed at this time. Foci of degeneration are tnost cotnrnon after the molt, to Form I, and this would imply that the hormone level is higher during this period than during the period of differentiation of (lither the testis or the secondary sex characters. This explanation is not consistent w&h the conclusion of Kittg (1964, 1965a, 196Fib) tltat no evidence to support holocrine secretion was encountered in the androgenic gland of 12 crustacean species examinecl by both light and electron microscopy. In most’ species King did not, observe differcncw between cells in different areas of t,tte gland or at different seasons with tltc exception that. the androgenic gland of the crayfish, P. da&i and P. frowbridgi, degenerate and possibly disappear during tltc winter. The attdrogenic gland of 0. nais is always present, alt’hough the massive clcgetteratiott obscrvcd in older animals fotlo\ving the lat,e summer molt to Form I might lead one to suggest its possible disappearance. King (1964) interpreted the data of Charniaux-Cotton, “to he good c?-idetirc for a secretory cycle, hut not necessarily ottc involving holocrine secrction.“ If this intcrprctatiott applies in 0. nnis, then the small, dense cells must he assutt~rtl to have sufficient activity to accouiit for tcst’icular growth and sperntatogenesis. The increased act.ioit,y of the gland prior to the tnolt to Fortn I can he acroutttcd for on the hasi:: of the increased size of tltc gland attd,,/or the increase iii the ttunit~et of tltc larger, vesicular, ant1 prcsutttahly tttore active cells. Tltc~ dcgcncrate areas, in ttii:: cxplnnntioti reprcsrttting the terminatiott of the secretory cycle, correlate well with this wlietne in that tltcy arc ohwrrcd only rarely during the proliferatire phase of the gland, increase in frequency and area prior to the ntolt to Form I, attd are most comtnott and (lxtettsive in the fall after the molt t,o Form I. It is possil)lc that holocrinc secretion does occur hut, that not all cell degcncratiott wtt he cquatted with secretion. Rcproductivc~ activity and slwtmatogcttcv+is are albent during the witttvr. nl-
I .?(i
(‘.ZHPEiV’EK
though apcriit arc rctaittcd itt tltc, vitclcfc~retis. The attclrogc~nit &tttd dc’rr~‘xI(‘.~ iii size, and tltc~w i:: a taciturn to ltrirti~ttd~ the stt1al1, clrwsC ccl1; hoTw\~C’r. NlJlC of thf* Ltrgcr, vesicular cells reinaitt in the glancl of approxini;ttcly 50% of the crayfialt. Tltcs :tttdrogcnic anIl thcs gland rllor]hologp ~)r(wtic~~ of ycrni ill t11c v:ts d(‘f(‘lY*tld itttlicatc a prolmblc brief rvttmal of I)IYYYIitig activity iti RIarclt in 0. UOI’Sas hit; 1w11 rcyortrd for 0. prop67~fp~s (Van Ikvcnt(~r. 19371. Adt tltc tirrw of thv ~mldatioti tiiolt from Fort11 I to Form IT iii April or 112iy. t hc~w is ;I good corrc~latiott lwtwcctt tlitt tttorpholog~ and histology ant1 tlw ltr(s~11111~~ :wtivity of the :kJtt~J’ogcrlicb gl:t~lcl; tlw glatttl is sinall. :dtllougll it) tl(‘V(‘J’ I’(‘gwssw
t,o tllcb
size
of
the
~)rc’viotts
The HU~~IJ~I(~J~ I)t*olifvrntiott gc>ttic gland appc’ars t,o ovwr olticr animals than iii t hv first possibly lwcnus~ th(a itttmttolt, WCOlld
eyclc
in pr0pinqt//~3
1llOlt C\-C‘l(s is ShOJtPl 0. n0ls as has IJccw f v2tll r)WVJlkT,
s~ttJltlt~~r.
of tltca ;t~~tlrocl:trliw itt thcl year atiitriwl~, pcriwl of tltcl
that1 tllc, fir.4 rcyortccl for (i. 1937 1 1 UlpOt’-
twntly, urtlikv first, yar wayfish, tto stn:tll. clcrtse cell:: wJtiain in t,llcb :tntlrogctlic glntlcl of tht> older minds:. Ttt addition, unlike the, first year Crayfish. the aticlrogc~nic gl:trt~l of sccottcl cpc~l(~nninials untic~rgow niassivc~ tlvgetwratiort with t,lw irtvasiott of thp gland l)Y ttutticrott.~ Ixtso~~lliliC :itld ~~ositlo~~ltilic~
.\NI)
I)Elt~)os
CRAYFISH
ANDROGENIC
1). 1%. (1959a). On thr sexual biology of I’trrdulrrs borealis (Crustacea Decapoda) I. Histolom of incretov elements. J. i%lnriw Biol. Assoc. TJ. K. 38, 381-394. C'.W,ISLE, D. B. (1959b). On the sexual biology of I’~~nduhs borenlis (Crustacea Decupoda) . II. Thrx termination of the male phase. J. Mrtrine Hit,/. Assoc. 7:. K. 38, 481491. (‘H ~HSIAUX-COTTOP~, H. (1954). Ddcouverte chez 1111 Crustacb .1mphipode (Orchestirc ycrmmarelln) 11’\1ne glandv endocrine responsablc de la diffkw~iation dcs curactkres sexuels primnires et .~c~~wndaric~ nr~lc~:. (‘o,nl)(. Reud. ilctrtl. Sci. 239, iS(k782. ClI-\flSIAIX-CIO'J'TO~i. H. (1957) Morphologic dc 1:~ &ndc androgknc chez Orchestia gammadn (*I (‘r~rcirdm mu(fnm. Bull. Sot. 2001. Pmnce 82, l(93. C’rr ~KSI.\I~X-CUT~WS, H. (1960). I,a glandr androei)nr> till Crusta& Stomatopode: Squilln mn~~tis. &jr//. Sot. Zool. Pr.ance 85, 110-114. C~.\~~rar:.u-(‘o~~os, H. (1962). Androgenic gland trl crustwfww. GIY. (‘amp. Bndocrit~ol. Suppl. 1, 241-247. ct, \KS1..\1x-C(O.rTos, H. (1965). Cont.Gle vntlo~.rmivn tlr la tliff&enciation sexuellr chez lea lTli,~t~:t(~P~ supkieurs. Arch. A/l//l. Microsc. .1/wpho/. Eq. 54, 405415. C‘II \ItNI.4I-s-(‘OTTos, H., .$SD KLEINHOLZ, I>. H. I 1%4). Hormonw in invertebrates other than III.YIB, /r/ “The Hormones” (G. Pincw. Ii. V. Tl~im:mn. and K:. B. Astwood. ~1s.). Vol. 4. pi,. 1X%198. .\c~a~lcrriic* Press. Nrw York. C~IRLISIJC.
('II
\l{~l\l's-C‘OTl'O.\-.
H..
ZERBIB.
c..
ASI)
I.‘7
GWND
ph~siologiquw clir,z Oniacoides Z’orcellio t/i/~trtfus et Hel/ericr brezicornia. Coopt. l?f~r/ri. Acrid. Sri. 258, 2197-2199. KING. D. 8. (1964). Fine struc*ture of the androgemc gland of the crab, Pnchygrnpsus crnss~,w~. Gen. Camp. EndocrinoI. 4, 533-544. KING. D. 8. (1965a). Comparative morpholog> of t.tre crustacean androgenic gland. M. I\. Disscrt~ation, Department of Zoolog)-. 1’nivr)rsil> of California, I~erkrlep. KING. D. S. (1965b). Ultrastructure of thv crust,acean andropcnic gland. ilnarr. Zoologist (Abst iwt,) 5, 672. LF:GRASI). J. J. (1958). Mise en Pvidencr histolopicluc Ct ctxpkrimcntalc d’un tksu androgknrchvz Oniscoi’dcs. Conzpi. Kent!. Acrrd. S-i. 247, 1238-1241. LEGRASD. J. J.. .~ND JUCHACLT, P. (1960). Mist en &idrnw anatomiclur: ~1, expkrimentjalr des glnndcs androgkws de Sphnrromn serrc~~~nc Fabricius (Isopode Flabellifbrc). (‘on~pt. Herrrl. Acrrrl. Sri. 250, 3401-3402. bX:RAXU, J. J., .\ND .JUCHAT:LT, P. (1961). l
&USY.
.I .I. (1!)66). Monographie de la glande androglow (1~ c*rust:c& rup&rurs. Crustncetrnn 10, 113-136. IhIEWY. 1\T. (l(960). Diffkrenciation ties voirs yc:nit:~.lw lllnlri du Crabr (‘nrci,~~s mrrerlrrs l,~nn&, Ri,lc dl>s ~~6tlon~~dcs ornlnircs. Cnh. Biol. .\/,,I-. 1, 2X&278. DEMEI.ST. N.. .\sI) VEILLET. A. (1958). Influenw (I(, l’ablation dcs pkdonculcs oculaires SW la rl:~ndf~ tintir.o&r dv (Inrcirf cc.9 vwrilns I.. t’ompl. Kc,r,rl. ;Icotl. Sri. 246, 1104-1107. 111 \ E.z~:. J. (1957). Donn6es llistoph3-siologiclues ‘lir 1:~ glandr androgitne de Nebnlin geoffroy,i. :I J-A. Atl~tl. Micr(/,~/~. Morphol. Ex~. 46, 199-209. GAM:HE:H. A. E.. AND KOZLOFF, E. N. (1964). “kk~ntials of Practical Mirrotechnique.” Lea :md l’cbigrr. Philadelphia. ( :H 41:. P. (1962). IntrrsrxualitG ct glande sntlrogkw vtlw O~~~rwc/rs limosus (Rafinesque). Ck~stn(‘( ,LIUL 4, 151-157. .II~~~I~Ac:LT. I’.. +xu ~,E::RASD. J. J. (1964). Transi.1 irm:il iof1 dl, ff~rncllrs gbnktiques vn mklfw
D. crayfish trsticular Dclwknent
(1964). Experimental studies on androgenic gland in wlation to function. Doctoral Dissertation. ot’ Zoologp, I-nivwGty of Virginia. SCUDIMORE. H. H. (1948). Factors influencing molting and sexual v~c*lcs in the c~ragfish. Biol. Bull. 95, 229-237. STEELE. M. (1902). The cra?.fish of Missouri. I./rift. Cincinntrti Bull. Srir. 2. 10, l-53. T.wri. P. I. (1941). The life history and rcolog~ of the wa~hah Cnmbnrrcs zm nl~,m.,.‘, ArnC’T. Mid/. Sutur. 25, 420446. TCHOIAICIAS. R.. K., AND RICICHARD, S. M. (1964). .\ possible androgenic gland in (?n/lir~~tes rccpidtts Rnthhun. Amer. Zoc~/ogGt (Ahstrart) 4, 383. TURXXR. C. D. (1966). “Cknrral Endocrinology.” 3~1 cd. IV. B. Saunders. Philnd~~lphia. 77~s DIGVENTER. TV. C. (1937). Studks on the I)ioloyof tlw clxyfish CnrrLh7r.s pmpir1c/w/s Gir:irti. U1. fjiol. .2lor/og,. 15, 147. PTTTKETT. the
H.
AX,)
Seasonal
(‘OMP~R.I’l’lVI~:
I’:SD:)(‘IlISOLOGY
15,
143-157
(1970)
Morphology and Histology of the Androgenic Gland of the Crayfish, Orconectes nais
bI:rle OrcotLec6es TK& were hatchrd in the spring and completed an unknown number of Form II growth molts during the summer. The population molt from the sexu:llly inactive Form II to the sexually active Form I occurred in late -August and c:nly- Scptcmber. The populntion molt from Form I hack to Form II occurred in the sl,ring. Some males, smaller than the norm for the population in late summer. remained in Form II during thrir first year and completed the first molt’ cycle in their sccontl year. Crayfish older than 1 year represented a small percentage of the population ; lrowcvcr. the limitctl datn establish that, some males complete more than OIIC molt cycle am1 more than one period of reproductive act,ivity. The antlrogenie gland of the youngest crayfish examined consisted of a small nmnl)cr of small ~11s with dcnsc. homogrncous cytoplasm and closely associated \vit 11 the, \‘:r;r‘ tlefcrcns ; no foci of ecllular degencrat,ion were observed. The androgenic ~l;md incrcanctl greatly in sizr tlurin, n the summer. The gland proliferated as a shcctlike% :ur:mgcmcnt, of mnsscs of cells and pnrnllrl and annstomosing cords; however. the 41s cnlargctl only slight,l~- and the c~ytol)larm rcmaincd homogrnt~ous. C)cc~asion:d foci of cellular dcgcncrat ion wcrc observed and invol\.ecl from as few as two cells to :I niu~11 Ixrgcr numhcr. Thr androgcnic~ gland at,t:rined its maximum size a wrck or t\vo prior to the t)opul:rt ion molt from Form II to Form I. The gland changed from tlrc Ilrc\.iott* shcrtlikc arrangement to onr of rntwined cords. Further, the ~11s were anti eontaincd vesicular cytoplasm ; areas of cellular deI:ugfl~ hyp~~rtrophictf gcncmtion were hot h romnmn nn(l cxt endive. ‘I’(3ticul:u m:rturation ;ui~l ~;l)c’rnl:Llopc,nr~ia occurred fxrly in the summci-, an(l g~~rrcr:dl~spermatogcnc& wad ahsrnt in Bngusl,. although sl~erm wcrc ret,ained in the V:W tlcfcren~ during the winter. Thus, tcst,iculnr activity largely preceded the t)rolifcr:ttion of the nndrogrnic gland and occur& whrn the androgenic gland conl:rinc~cl t)rirn:nily tlrc small eelI :mtl only oc~c:lsionnl arcas of cellular degeneration. The, nlolt from Form 71 to l’orni I nml ttlci suhscclucmt tlcriotl of rrproducti\-c activity W’K nssociatcd Tvith an androgcnic gland of maximum size that contained l~rim:uily 11?I)c,rtrol)hic~ri eclls wilh vesicular cytoplasm and numerous, cxtcnsil-c arc:rs of cellular dcgscncration. Tlrc ohsemations intlicatc that, tlrc ;mdrogenic~ gland posscsscs sufficient a,rtivit> prior to and during its tlroliferation to stimulate trsticular maturation and spcrmatogcnc>& l,rtt insufficient activity to stimulate the differentiation of t,he Form I gonopod ; thcb differentiation of the sesu;dly ;nt,ivc gonol)od and the rcpro(lu(,tivc’ rrctivity that, iollows the molt from Form II to Form I may occur in response to :m in(,rc:rsc in thr activity of the androgenic gland. Although some activity must IW :rssrlmcd for ills androgmir gland prior to and tlrtring the ljroliferation of the, gl:rntl. the ~11s rcq,onsihle for thcs activity remain unknown. If the foci of cellular hgpcrtrolh? and dcgrncration rcq)rrscnt holocrinc secretion. the small arcas of dcgenerat ion or~casionally ohscrvrd during the proliferation of the androgenic gland ~ot11d account, for the low level of activity suggested to be responsible for testicular tmttmation and sl)crmatogcncsiz ; the increase in the number of hypert.rophied cells im(l t 111’ more numerous and cxtmsivr arras of cellular dcpcnerat,ion could account 14:;
rq,ortcd the androgenic gland to bc of a holocrine t,ype, hut King (1964, 1965a, 19651s) did not find evidence to support, holocrine secretion. The purposes of the present study were to describe the androgenic gland of the (brayfish, Orconectes nais, and to determine ii thcx androgenic gland undergoes seasonal lnorphological and histological changes indicative of activity and related to reI)roductivc activit,y and the molt cycles of tllc animal. The molt and reproductive c.yclcs of crayfish species have lmw deicril-)cld by Steele (1902)) Ortman (1906), Van Deventcr (1937)) Tack (1941)) and Snutlamore ( 1948’). Jlalcs of the auhfamily ( ‘ambarinac cxhihit an cxternwl sexual which divides thr male climorphism I)opulation into sexually active (Form I) and sexually inactive (Form II) animals. .\Ial~ in their first summer of growth ~~ntlergo a sclricasof Form II molts. Reginlling with the first, molt to Form I, malts tnolt altcrnatcly between Form I and Form 1I during seasonal molt periods. Crayfish it) Form II are the functional cquivalcnt of protandric hcmaphrodites in the interrex .stattx that, posso~scs a testis hut, no copuiatorp organs. Thus:, if the androgcnic gland I*ontrols male sexual differentiat,ion in the c~rayfish, one might expert a c~orrclation l)et,wecn androgenic gland morphology and t tl(h morphology of the secondary SC’schar;ictcbrx and the testis. MATFXIAW
AND
METHODS
d ~~ZmaIs. Male cravfish were colleckd by srlinc from ponds locatcvl in Boone County. Missouri. (‘myfish ww prrs~~~l from mid-June. 1965. i.hrough Drccml)er. 1966. The numbrr of animals r~ollvctcd varied with thrir availability. Ten to 20 malts wcrc llrcsfvod per collection date when Ijos*ihlc ; howrvrr. midwintrr collections wcrc (sornl)oscsd of only t,wo or thrcr animals prr rolIvction datr. T>uring the following l”riods c-rayfish we’re prrscrvrd from a stock which was n~:tint.:rinrd in the laboratory for periotls ranging iron1 2 we&s to 4 months: Octobrxr, 1965, through I~‘&nu~rq’, 1966 ; Junr through mid-August,. 1966 : Novfvlbcr through December. 1966. Laborator> :mimals w<‘rc krpt, at, room tmmprmturr in running rap watclr and wrrc fed liver once a wrrk. Animals \vvrv st~l~c~lc~~l and prcsr,r\.xl fxm c’:rc,h siz:l (*la88
I,rf~sf~rrl. 111 the scinc or actuarium and 7lol on t,lle basis of their numbers in the population. ‘I% form and ccphalothoras length wrre recorded for and year rl:~sscs wf’r(’ each pwf~rvcd animal, assigned on t,hf) b:r& of ;iizr. animal wit* op~nr~l ‘I’issue I’reprtrfim. Thv ventrally to assure rapid fixation of thrl rqxoduvtive organs and androgenk glands. E‘ollowiue fixation in neutral formalin. t hc cxr:q~:icv dorn:d to the fourth and fifth prripods was rcmovcttl and the \-as dcfrrrns rut, to l)rcTvcnt to:ikp. ‘1‘11(’ fourth and fifth legs WV(W disarticulutc~d a~ :L r~nil and the coxapoditrs staincvl with 0.5’4 mvt tryknc, blue to bring out muscular d(ltail anti to ln:k(~ the androgcnic gland xisibl~. The va:: dofvrvns (in the fifth lrg) was cut, :mtc>rior to thv &inning of the cnlargetl mus(&ir portion. and t11(! cvnt ire, post&or ~-as dclfvrvns ivas rvmo\-rvl. ‘1’11~ :m(lrogrnic gland is tlificult to r(vlo\-fx cvnll)l<>ttily IN’cause: of its diffusr nature: l)ortions 0C thv glxlcl frequently :II’(~ not. firmly :Iltac~~lf~tl to 111v 1 :I* dtxfcrcyx+ anti cstcnd a c~on*iclc~tal)lr tlistanc~c, into thrl surrounding ronncctivr Iissue. Tlrv testis \V:S rt~movcd. and one lobt~ was processed histologicall> with thfl caorreq,onding :mdrogSc~nic~ gland. T(~mpor:lry whole mounts of vnsa drfcrcxtk :nl(l androgc~nic glands were staincvl 17ith 0.5’;; mPt h?lent’ I)lu~~. Prrmanmt, whole mounts \v(‘rv rlvIlydratrsd in alcohol ant1 Stain& with I.yncll’s precipitated borascarminc~ (Galigher :md lioz!ot’f. 1964). Rcrial par&n sect ions of andl,og(>nic* glands and thv vorrcst)oncling t(vtPd wart’ rut at. 10 ,U :mtl stained with Harris hrmatosplin and rosin. .\letltoc/ of S//rt/y. Two svrirxs of obsc,rv:rtions wcrc mad(~ on t hv nndropc,nic* glands. In tllc, first scrims, tc~mporary whole mounts of entir.c> glands from at least two animals per collection (lattx wvrv r:tifvl m terms of t hvir r.c,lntivcx size and morlhology ; alkolutf~ m(~ikxircnlvnl of androgc~nic~ gland volume x:s not, frasiblc tiuv to the diffuse nature of ttw gland. Thr following rating systvnl was :i~~~)liivl to thr glands:
Tylv II. (Aand volume much grcxatcr than Typo I : lary& portion consists of :L shc~c~tlik~~ arrnngemcnt of masses of cells and paritllc~l or anastomosing cords which extc,nd from t hca V:W dcfcrcns into thr surrounding connctivc tissue. ‘\ small number of entxinc,d cords closely associatrd nith th(l Y:lS dvfrrcns also arr prcsrnt (Figs, 51, and 5c). Tyler III. Gland consists primarily of mntwinctl cords although gland ~olumc may be equal to Typrs II. Cords are present along the vas defrrens and arc associated with a large branching ncrvc some distance from thr vas dcferens; small islands
lctt:. deferens
1. Diagram of the male ivd), attdrogettit~ gland
reprodttciive Cage, and
systenl of 0. nuis getlila papilla igp I.
Aowittg
the
lot*:ttiott
(,f ttt(i
k&s
(I ,. va.
25 :t!td 35 mm cel~lialot.ltorax wrc itt tltcir first yrar hut had hatched unusuall;v wrly in the spring. Animals greater than 41 mm celthalothorax at any season wrc assigrtc~~l to tltc second year class, although it ib ltrol~al~lc t#hat, some of tltcw animals wvro in at lcast~ their third year of lift. III t,ltis possible third year ~~1:~s~wart’ w\w:tl animals grvilter than 45 mm ccI~lialotliot~~tx at the cttcl of the summer growing ,wiwott tltat orcr-wititc,retl in the lal~ot~a~ot~y.
Forty-out millimeter celA~alothorax was t Itv Gimatcd maximum size for animal> ifI their first year of life based on tlte tlktrihution of size classes during the sampling period (which included two summcm) of the (Fig. 21 and on observations ttumh(w of animals iii each size class in ltottds which were drained yearly. Clearly, iuxtty animals did not attain tltis nii~ximuiii size, nor did all animal:: molt to Form II hy tltcn (911 of tltc first growing season. Xtiitnal~ Iwtn-cvti 25 and 35 mm ccl~ltalot,lior:~x in intrrprc~tc~~l to 1~ .I 1111(’ ant1 .July wcrc >(wtt(l ywr crayfixli in their first molt, I*\-clc wlticlt had not reached population t1orms at tlw end of the prwious growing ..(‘:t~ou. Howcvcr, it is possible that. at least ..ottt(s of tlw .Junc and .July animals hetwccn
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FIG. present
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t~iorl~liology :kttd histology of the ntidrogc~rtit gland of t’lic crayfish arc’ presented itt Figs. 2, 3, and 4. The acasonal morphology artcl ltistology of tlic antlrogenic glantl :ut(l tlit, wasonal dcvcloltment of the tw:tis it1 crityfish in their first year map Jw sutttttt:trizo(l
July
I
I Aug
Sepr
I I Ott NO” Dee Month
I
I Jan
I Feb
, Mar
J Apri I
2. Relationship between size, form, and time of year in 0. nais. Each point indicates in the population. Solid circles represent Form II; open circles represent, Form I.
a size and form
Type II
TypeI,;y
:;
he
July Aug. Sept. Ott
:,
,
,O,-:
,
NW Dee Jon. Feb. Mar. Apr. May
E’I~;. :<. Relationship between androgenic glntrd morphology, form, alld time of year in 0. nrris. Ciwles represent, animals est.imsted to be iti t heil first, year; squares represent animals estimated If> be older than 1 year Solid symbols represent. animals in Form IT, fq~er~ symbols rrprrsellt :Itlimnlr ill Pfm~
1.
TYPOD
P Type A
June July Aug Sepl Or1 NW Der Jon
Feb Mar Apr
thy
YIC;. 3. Relationship between androgenic gland histology, form, alrd time of year in 0. nnzk. Symbol< as in Icig. 3. I>irec%ion c,f the arrow- indicates thr minor
f:ell
type
presellt.
149
FIG. 5. Whole mounts of the vas deferens and associated androgenic gland (arrows) in 0. nois. X7.4. (aj Minimal gland (Type I) from a June animal in Form II; (b) maximally proliferated gland (Type II) from an August animal in Form II; (c) initial development of entwined cords (Type III) from an August animal in Form II; (d) maximal developmentj of entwined cords (Type IV) from a Sept,ember animal in Form I.
1”1n. 7. Sectiolw of the alldrogellic gland in 0. nuis. (a) IJocxl area of degeneration loc:ited 10 I* from t.he area shown in Fig. 6:~. X525; (b) Xassive degeneratiotl of the gland (Type E) from a .\lay animal in Form 1. The darker cells ilr the right one-half of t,he photograph represent the invasion of the gland by basophils and eosinophils. X263.
tht> tcet,cs were filled with
sperm in late
.?\ugust.
‘1’1~ population molt from Form II to ForIn I took plncr in late August and early Scljt cwhcr in first year animals of at least
25 mm cephalot.horax. During this lwriod, the androgcnic ghml incrcaxd only slightly in total size, but the sheetlike area of the androgcnic gland decreased in Yolumc and the awa of cntwinotl cord:: in-
152
CAHPESTEH
creased in volutnc. By late September, the sheetlike area was reduced to islands or had disappeared entirely, and the androgenic gland of animals in Forrn I showed maxirnum devclol~mcnt of entwined cords (Typca III, Fig. !&I). The cords began posterior to t,he constriction on the convex surface of the vas deferens and continued posterior15 rotating 180” until they reached the bascx of the large nerve described above. Cords or islands of cells frequently were founcl also along several nerve branches sorn(’ distance from the vas drferena or (‘\-en oxtended along or between small skeletal tnuscle fibers; this portion of the gland often was lost in dissection or processing. Importantly. not all of the crayfiqh followed the populat,ion norm for molting. Tltcs majority of crayfish under 28 mm remainctl in Forrn IT throughout thr yrar. In addit’ion. four anirnals were exarninctl that wcrc at least 34 mm cephalothorax but were still in Form II in early Ott,ober. Of thcasc. two showed androgenic glands in the proliferative stage (Type II), and one showed tnaximally entwined cords (Types III) ; the remaining anirnal had a rcdurchcl androgenic gland (Type IV). In addition to the gross morphological changes of the androgenic gland, the histology also changed during the period which began at least 2 weeks prior t,o the first rnolt to Forrn 1. In two August animal:: in Form II and in almost all September attimals in Forrn I the dominant, cell type was Type C. These cells showed a definite ittcrease in cytoplasmic volume and a chattgr itt cytoplasmic character frotn relatively dense to mot-cl vesicular (Fig. 6b). Typta B rclls made up the remainder of the glattcl. Foci of dcgencration such as those drscrihcd above were common in the androgrnic glands of Scptcrnbcr animals itr Form I. Most testes taken frotn Form I animals in late August and early September had tZubulcs filled with mature spc’rnt, but spertnatogencsid essentially had cea9clcl I)\early Sept,ember. The majority of first. year animals caollectcd through the fall, winter, and carI> spring were in Form I (Fig. 2). Tltca attimala largely disappcarc~cl front tltcs opt’tl
AND
I)EHOOH
water as the weather ttrcatuc colder in thr. fall (,November) and wv(‘i’(’ not Itrcs(~u[ again until March; cott~eqttt~tttly much oi the data on winter attim& wt’r(’ tnkc.11 front animals maint,aittr>cl in the laboratory. During the period Oatobcbr through Altt:ii t>lte androgcnic glands of most, animals in Form I retnained as entwined cords (‘l’yl)ta III or Type IV with reduced volutntb) ; sottt(’ returned to thr shectliktb arrartgenit*tt! ( Typr II I Histologically Tyl~ (’ rr~mainc~(l I II(, clominant cell type during t,hc fall! although cells with maximum vcsicbular cytoplasm tTyltc> D, Fig. 6c 1 WIY present iti tltcj gland. Extensive area+ of ~11 degctrerutiotl (Typtb E. Fig. 6di also were present i11 ttlc, glantl of one Sovembrr animal. Thcx itttdrogenie glands of Forttt t (brayfish collocto(l cluritig Decetnbt~r t,hrough Jlnrch w~iy’ characterized by a r&urn to the sntdl (101~~ ~11s of Type B, although Type (’ ~11,s ~vct’(~frc~qucntly presc>tit a5 the minor WI i typo. Arcas of ‘I’ypcl (’ ill+ sltowr~rl t tit, usual irtcidencc of degt~ttcr:~tiott.
Tlrcb ltoltulat~iott tttolt frotrt Form I to Form II began itt Xltril aliti oorttinuecl through the Spring. Form I and II animals 1~s than 41 mm c~cl~li~~lotliorwx iti tltc, pc~rioclApril through ,\lay had sttiall attdrogettic gla~tds (Tyl~ I ;t~~tl l’g~w 11. I ; OII(’ Fort11 II c*rayfish hati :ttt ;Ltt(trogctti(’ gl:tl~rl iii tlici ltrolifcrativc *tage ITypc~ II 1. ‘Q-IN B was the dotninant ~11 tyl)(> in tlttl glan(lh of ;~ttimals in both FOIXI 1 anal Form I I tlurittg Altril :ititl Jlwy. \\.itlt on(’ ~~s-~:‘il)lr~ c~xcc~lttiott. 110 cxccssivc. tleg(~iteratiitn \vi~i t-rotc,d in tlicls(t gIantIs. The tc+tir \v:is not ox:ituiti(~~l cluritig t1ti.GI)~~rioct.
CK.4YFIBH
Ah-DROGENIC
tory and thus were know1 to lue in their second (possibly third) molt cycle and/or year. June and August Form I animals had reduced gland volumes and cells of Typv B, C, or D; no Form I animals were c~ollwted in *July. Second year animals in Form II in early summer had glands in the I)roliferativc phaw (Type II) and containr~d the *mall, dcnw ~11 (Type B). Ko second \-car crayfish wre arailablc during the critical Jwriod l~ctn~~~n late August and (SarIy October. .I11 second year or older animals cxamilled in late Octohcr through Dccemher WT’IY’in Form I. as wcrc t)hc majority of :mimals in the first year cycle (Fig. 2’1. Th(w large crayfish were collected when 11pond was clrained. Most’ of these crayfish hacl reduced androgcnic glands (Type IV 1, :m(l the remainder had glands of Type II or l’ypcl III. Kith two excrptions, all ani~nals cxaminc~cl from October through April in tjot,h Form I and Form II had glands which ww composed of highly vesicular wlln with large areas of dcgcncration I Tylw:: 1) aud E:), and beginning in .Jwlluary almost all glands showecl maxi1~1111dclgencration (Type E) However. it mwt lw notcacl that while degeneration was witl(qwatl in thaw glands, it was never wniplc~t~~; tlww ww always many ~11s I)rt,..c,nt8which appc~arcti normal. (My a few crayfish were examinctl in 11:~~ at the crd of their second or third year. OIIC Form II animal had an androgenie gland of maximum dcvelopmcnt t Tylw III). Examination of a gland from a Ilay animal in Form I and one’ in Form II ~how~l maximum clcgencration (Type rc 1. ~;l)crrilat’ogciiesis did ocwr in the testis of son1~~animals in at least their wco~~d molt (cyclic. Spc~rmatogenic activity was present in t hv t&is tubules of Form II animals in lwth .Junc anal .July. Howcrcr, two Form I ;tninials which wrv examinetl in .Junc (lit1 not dcmonstratv ~pcrmatogenesis. No twtc,s wwc c~xaniinetl for spc,rriiatogcrlic, activity iii August or Srptcn~her. Mwturc qwrni wcrc prcs;cnt in thfs testis of Octolwr anin& in both Form I and Form II. Tlw test is was rcgrc5wtl in gross appearance ill nio,-t Novcnib and Dtwmher animals iii
GLAXIII)
153
Form I. although mature sperm frequently were present in the vas dcfcrens of winto] animals. X0 animals were examinetl for testicular drvclopment from .Januar> through May. No method has been dcwloped to accurately age crayfish or to tletcrminc thv numbci of molt, cycles and assoriatcd periods of reproductive activity completed by an individual crayfish. In the ahscnw of information derived from animals of known age, size is a logical criterion to use. Crwyfish larger than the maximum size attained by the population at, the wtl of the first year, estimatcvl to 1~141 mm cephalothorux for 0. nais, can reasonahly hv assumed to be in at least their second year of life. Tlit~ possibility that a frw individuals eiitr~~ their third year of life is suggested 1)~ thv large dizc of some crayfish in the spring. The majority of crayfish complete the first molt cycle and the assoriatcd pcriotl of reprocluctivc activity in thrir first ywr; howvcr. at least. sonic animals appear to remain in Form II throughout thv first year and complctc the first molt cycle in their sccoud year (SW lwlow) In addition. the data indicate that soiii~~ crayfi.;h cornpletc, more than one molt cycle and mor(1 t81ian one period of reprotluctivc activity. Thv extent to which more thtan one molt cycle and pwiod of wproduc$ivc a&vity occurs in t,lic J~opulation was not iuwetigated and remains 2111 intcrwting and important question, particularly ar it rclatw to androgenic gland coutrol. &low than one molt cycle anal rcproductivc~ period also liavc lwrn reported for Cnmbrrrus ‘oDsc7c1.1~~ (Ortmann, 1906) and 0. (C~nmbnr7~n) pfoping7rus I Van Del-cntc>r, 1937). Ollly 0Ilc molt cyclr and 011~‘ r(‘productive period, generally over a 2-y(aai period, is rcport~ctl for 0. (Pam6nru.s) iv/nzunis (Tack, 1941 1. The androgenic gland of 0. nnis is similar to that of other wptantian dcc*apotl~ with regard both to it.< location and its nlorJ~llology and histology (rf. rwiem i)y Charniaux-Cotton et 01.. 19661, and 110 romrnrnts in addition to the doscriptioii prcsrntrd in tlirb Kwults aplwar wari-antclcl.
CR.ZYFISH
ANDROGENIC
IL to Form I and the subsequent hrecding behavior occur in response to an elevated hormone level. An explanation based on different t,hresholdx of tissues to a hormone and changing le\-cls of the hormone is not without precedent, and is well documented for the thyroid and the control of amphibian tttetatnorphosis (Turner, 1966). In addition, I)cmeusy and Veillet (1958) reported that I)ilat,eral eyestalk extirpation of C. maenas rwults in the sitttultaneous hypertrophy of the androgcnic gland and precocious growth of the reproductive organs. A seasonal and progressive lifting of cyertalk itthit)ition would provide the mcchatGtn for the suggested rise in the secretiott of the androgettic gland hormortv. \\Me it appears clear that some act,ivitp must 1~ assutncd for tltc androgenic gland Iwforcs and during it:: proliferation, the cell typch rwpotisihle for the secretion of the ttortttottc remaitts uttattswercd. CharniauxCotton and her co-worker:: (Charniaux19.54. 1957. 1962; Charniaux(lotton. Cotton et nl.. 1966) have dcscrilwd the following ~11 types itt diffcrcnt areas of t tte crustacean wndrogettic gland : small. ~lctt:‘(~ ~11s without cyt’oplasmic vacuoles, largcjr cells with vesicular cytoplasm, and cell- in various stages of degeneration. Ttt(w authors c~oticlurlcd that the attdrogettic gl:md wcretcs in a ltolocrinc mattn(~r. Itt 0, Tunis ttiv increase in cell size. ttic ch:tngw in cell tttorpliology, and the ultitnat(b degettrrntiott of t,hc cells are consistent, with holorrinc~ scwetiott. Further, fori of clvgc~ticwtiott arc’ always prcwnt and Y:try ira~onall~ iii nutiilwr and area. hltltouglt loc:~lly clegcncratc area8 do not appear to ltav,, :I constant locatiott in the attdrogcnit qlatltt, the degenerate area is oftctt periph(BraI to a mass of dense cells. A rimilar at*r:ittgt~tncnt iii Cnllinectes strpirlris wils intc~t~prctcd tw Tcholakian and Rcirhard 11964) to inriicatc holocrinc secretion. If tltcb local areas of degeneration ohier\.cbtl it) the attdrogcttic gland of 0. rlnis rcq)rcwttt holocrinc wcrctiott, tltc mall ttutnlwr of local areas of cell ltypwtrophy ant I tlt~gcwcration ohserved in the growing ;ut(Irogcttic gland of Form II crayfish could account for the low hormone conrctttration iuggwtctl to lw rc~spottsiblc for twticulnt :lc.ti\,ity : thv itt(wawd titer of hormone
(:T,.iNI)
lpi.5
suggested t’o occur prior to the Form II to Form I molt may be produced by the more extensive and more common areas of cell hypertrophy and degeneration observed at this time. Foci of degeneration are tnost cotnrnon after the molt, to Form I, and this would imply that the hormone level is higher during this period than during the period of differentiation of (lither the testis or the secondary sex characters. This explanation is not consistent w&h the conclusion of Kittg (1964, 1965a, 196Fib) tltat no evidence to support holocrine secretion was encountered in the androgenic gland of 12 crustacean species examinecl by both light and electron microscopy. In most’ species King did not, observe differcncw between cells in different areas of t,tte gland or at different seasons with tltc exception that. the androgenic gland of the crayfish, P. da&i and P. frowbridgi, degenerate and possibly disappear during tltc winter. The attdrogenic gland of 0. nais is always present, alt’hough the massive clcgetteratiott obscrvcd in older animals fotlo\ving the lat,e summer molt to Form I might lead one to suggest its possible disappearance. King (1964) interpreted the data of Charniaux-Cotton, “to he good c?-idetirc for a secretory cycle, hut not necessarily ottc involving holocrine secrction.“ If this intcrprctatiott applies in 0. nnis, then the small, dense cells must he assutt~rtl to have sufficient activity to accouiit for tcst’icular growth and sperntatogenesis. The increased act.ioit,y of the gland prior to the tnolt to Fortn I can he acroutttcd for on the hasi:: of the increased size of tltc gland attd,,/or the increase iii the ttunit~et of tltc larger, vesicular, ant1 prcsutttahly tttore active cells. Tltc~ dcgcncrate areas, in ttii:: cxplnnntioti reprcsrttting the terminatiott of the secretory cycle, correlate well with this wlietne in that tltcy arc ohwrrcd only rarely during the proliferatire phase of the gland, increase in frequency and area prior to the ntolt to Form I, attd are most comtnott and (lxtettsive in the fall after the molt t,o Form I. It is possil)lc that holocrinc secretion does occur hut, that not all cell degcncratiott wtt he cquatted with secretion. Rcproductivc~ activity and slwtmatogcttcv+is are albent during the witttvr. nl-
I .?(i
(‘.ZHPEiV’EK
though apcriit arc rctaittcd itt tltc, vitclcfc~retis. The attclrogc~nit &tttd dc’rr~‘xI(‘.~ iii size, and tltc~w i:: a taciturn to ltrirti~ttd~ the stt1al1, clrwsC ccl1; hoTw\~C’r. NlJlC of thf* Ltrgcr, vesicular cells reinaitt in the glancl of approxini;ttcly 50% of the crayfialt. Tltcs :tttdrogcnic anIl thcs gland rllor]hologp ~)r(wtic~~ of ycrni ill t11c v:ts d(‘f(‘lY*tld itttlicatc a prolmblc brief rvttmal of I)IYYYIitig activity iti RIarclt in 0. UOI’Sas hit; 1w11 rcyortrd for 0. prop67~fp~s (Van Ikvcnt(~r. 19371. Adt tltc tirrw of thv ~mldatioti tiiolt from Fort11 I to Form IT iii April or 112iy. t hc~w is ;I good corrc~latiott lwtwcctt tlitt tttorpholog~ and histology ant1 tlw ltr(s~11111~~ :wtivity of the :kJtt~J’ogcrlicb gl:t~lcl; tlw glatttl is sinall. :dtllougll it) tl(‘V(‘J’ I’(‘gwssw
t,o tllcb
size
of
the
~)rc’viotts
The HU~~IJ~I(~J~ I)t*olifvrntiott gc>ttic gland appc’ars t,o ovwr olticr animals than iii t hv first possibly lwcnus~ th(a itttmttolt, WCOlld
eyclc
in pr0pinqt//~3
1llOlt C\-C‘l(s is ShOJtPl 0. n0ls as has IJccw f v2tll r)WVJlkT,
s~ttJltlt~~r.
of tltca ;t~~tlrocl:trliw itt thcl year atiitriwl~, pcriwl of tltcl
that1 tllc, fir.4 rcyortccl for (i. 1937 1 1 UlpOt’-
twntly, urtlikv first, yar wayfish, tto stn:tll. clcrtse cell:: wJtiain in t,llcb :tntlrogctlic glntlcl of tht> older minds:. Ttt addition, unlike the, first year Crayfish. the aticlrogc~nic gl:trt~l of sccottcl cpc~l(~nninials untic~rgow niassivc~ tlvgetwratiort with t,lw irtvasiott of thp gland l)Y ttutticrott.~ Ixtso~~lliliC :itld ~~ositlo~~ltilic~
.\NI)
I)Elt~)os
CRAYFISH
ANDROGENIC
1). 1%. (1959a). On thr sexual biology of I’trrdulrrs borealis (Crustacea Decapoda) I. Histolom of incretov elements. J. i%lnriw Biol. Assoc. TJ. K. 38, 381-394. C'.W,ISLE, D. B. (1959b). On the sexual biology of I’~~nduhs borenlis (Crustacea Decupoda) . II. Thrx termination of the male phase. J. Mrtrine Hit,/. Assoc. 7:. K. 38, 481491. (‘H ~HSIAUX-COTTOP~, H. (1954). Ddcouverte chez 1111 Crustacb .1mphipode (Orchestirc ycrmmarelln) 11’\1ne glandv endocrine responsablc de la diffkw~iation dcs curactkres sexuels primnires et .~c~~wndaric~ nr~lc~:. (‘o,nl)(. Reud. ilctrtl. Sci. 239, iS(k782. ClI-\flSIAIX-CIO'J'TO~i. H. (1957) Morphologic dc 1:~ &ndc androgknc chez Orchestia gammadn (*I (‘r~rcirdm mu(fnm. Bull. Sot. 2001. Pmnce 82, l(93. C’rr ~KSI.\I~X-CUT~WS, H. (1960). I,a glandr androei)nr> till Crusta& Stomatopode: Squilln mn~~tis. &jr//. Sot. Zool. Pr.ance 85, 110-114. C~.\~~rar:.u-(‘o~~os, H. (1962). Androgenic gland trl crustwfww. GIY. (‘amp. Bndocrit~ol. Suppl. 1, 241-247. ct, \KS1..\1x-C(O.rTos, H. (1965). Cont.Gle vntlo~.rmivn tlr la tliff&enciation sexuellr chez lea lTli,~t~:t(~P~ supkieurs. Arch. A/l//l. Microsc. .1/wpho/. Eq. 54, 405415. C‘II \ItNI.4I-s-(‘OTTos, H., .$SD KLEINHOLZ, I>. H. I 1%4). Hormonw in invertebrates other than III.YIB, /r/ “The Hormones” (G. Pincw. Ii. V. Tl~im:mn. and K:. B. Astwood. ~1s.). Vol. 4. pi,. 1X%198. .\c~a~lcrriic* Press. Nrw York. C~IRLISIJC.
('II
\l{~l\l's-C‘OTl'O.\-.
H..
ZERBIB.
c..
ASI)
I.‘7
GWND
ph~siologiquw clir,z Oniacoides Z’orcellio t/i/~trtfus et Hel/ericr brezicornia. Coopt. l?f~r/ri. Acrid. Sri. 258, 2197-2199. KING. D. 8. (1964). Fine struc*ture of the androgemc gland of the crab, Pnchygrnpsus crnss~,w~. Gen. Camp. EndocrinoI. 4, 533-544. KING. D. 8. (1965a). Comparative morpholog> of t.tre crustacean androgenic gland. M. I\. Disscrt~ation, Department of Zoolog)-. 1’nivr)rsil> of California, I~erkrlep. KING. D. S. (1965b). Ultrastructure of thv crust,acean andropcnic gland. ilnarr. Zoologist (Abst iwt,) 5, 672. LF:GRASI). J. J. (1958). Mise en Pvidencr histolopicluc Ct ctxpkrimcntalc d’un tksu androgknrchvz Oniscoi’dcs. Conzpi. Kent!. Acrrd. S-i. 247, 1238-1241. LEGRASD. J. J.. .~ND JUCHACLT, P. (1960). Mist en &idrnw anatomiclur: ~1, expkrimentjalr des glnndcs androgkws de Sphnrromn serrc~~~nc Fabricius (Isopode Flabellifbrc). (‘on~pt. Herrrl. Acrrrl. Sri. 250, 3401-3402. bX:RAXU, J. J., .\ND .JUCHAT:LT, P. (1961). l
&USY.
.I .I. (1!)66). Monographie de la glande androglow (1~ c*rust:c& rup&rurs. Crustncetrnn 10, 113-136. IhIEWY. 1\T. (l(960). Diffkrenciation ties voirs yc:nit:~.lw lllnlri du Crabr (‘nrci,~~s mrrerlrrs l,~nn&, Ri,lc dl>s ~~6tlon~~dcs ornlnircs. Cnh. Biol. .\/,,I-. 1, 2X&278. DEMEI.ST. N.. .\sI) VEILLET. A. (1958). Influenw (I(, l’ablation dcs pkdonculcs oculaires SW la rl:~ndf~ tintir.o&r dv (Inrcirf cc.9 vwrilns I.. t’ompl. Kc,r,rl. ;Icotl. Sri. 246, 1104-1107. 111 \ E.z~:. J. (1957). Donn6es llistoph3-siologiclues ‘lir 1:~ glandr androgitne de Nebnlin geoffroy,i. :I J-A. Atl~tl. Micr(/,~/~. Morphol. Ex~. 46, 199-209. GAM:HE:H. A. E.. AND KOZLOFF, E. N. (1964). “kk~ntials of Practical Mirrotechnique.” Lea :md l’cbigrr. Philadelphia. ( :H 41:. P. (1962). IntrrsrxualitG ct glande sntlrogkw vtlw O~~~rwc/rs limosus (Rafinesque). Ck~stn(‘( ,LIUL 4, 151-157. .II~~~I~Ac:LT. I’.. +xu ~,E::RASD. J. J. (1964). Transi.1 irm:il iof1 dl, ff~rncllrs gbnktiques vn mklfw
D. crayfish trsticular Dclwknent
(1964). Experimental studies on androgenic gland in wlation to function. Doctoral Dissertation. ot’ Zoologp, I-nivwGty of Virginia. SCUDIMORE. H. H. (1948). Factors influencing molting and sexual v~c*lcs in the c~ragfish. Biol. Bull. 95, 229-237. STEELE. M. (1902). The cra?.fish of Missouri. I./rift. Cincinntrti Bull. Srir. 2. 10, l-53. T.wri. P. I. (1941). The life history and rcolog~ of the wa~hah Cnmbnrrcs zm nl~,m.,.‘, ArnC’T. Mid/. Sutur. 25, 420446. TCHOIAICIAS. R.. K., AND RICICHARD, S. M. (1964). .\ possible androgenic gland in (?n/lir~~tes rccpidtts Rnthhun. Amer. Zoc~/ogGt (Ahstrart) 4, 383. TURXXR. C. D. (1966). “Cknrral Endocrinology.” 3~1 cd. IV. B. Saunders. Philnd~~lphia. 77~s DIGVENTER. TV. C. (1937). Studks on the I)ioloyof tlw clxyfish CnrrLh7r.s pmpir1c/w/s Gir:irti. U1. fjiol. .2lor/og,. 15, 147. PTTTKETT. the
H.