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The fungi of germinating farm seeds
was filled up for ornamental purposes by a frill of coloured paper. I n the months of September and October a succession of Coprzni came up in the flower pot amongst the roots and between the stems of the Aspidistra. At first these attracted little notice, but after a time they were more carefully examined and proved to be C. domesticus Fr. Further investigation led to the flower pot being lifted out of the vase. I t was found to be covered with the yellow hyphze of Ozonium, as well as the brick and block of wood upon which it stood. The hyphae were seen entering the opening at the bottom of the flower pot and the larger openings in the bottom and sides of the porous earthenware of which it was formed. These hyphze had grown up through the mould until they reached the light and produced their The associasporophores oil the surface as before described. tion of Ozonium with Coprivtus had been observed in the spring of the same year. In West Briggs Wood, Wormegay, a decaying stick was found with a Coprinus on its upper side and a mass of Ozonium on its lower. No very careful examination was made at the time, so the species was not noted, and it may have been C. domesticus, but it is more likely that it was the frequently overlooked C. similis of Berkeley and Broome. It is probable that other mycologists have noted the association of Oaonium with Coprinw, but I have been unable to find any published account of their observations.
THE FUNGI O F GERMINATING FARM SEEDS. By A. Lorrain Smith. PLATE IX.
For the last two years I have been assisting in the botanical work undertaken for the members of the Royal Agricultural Society by the consulting botanist, and during that time I have had a .great deal to do with testing the germination of grasses, clovers, and other farm seeds. If the seeds are slow in germinating or unsound, they are liable to be attacked by various fungi, and it has been interesting to note the constantly recurring moulds. The saucers on which the seeds are germinated are thoroughly cleansed by immersion in strong acid solution, and by subequent washing and scrubbing. It is impossible in such
work absolutely to preclude fungoid infection from the surrounding atmosphere during the progress of germination; but all ordinary means are employed to secure cleanliness and speedy growth of the seeds ; and the evident conclusion is that the spores of most of the fungi that develop in the germination case have been brought into the laboratory with the samples. The rough pods of sainfoin carry most spores, and become very thickly covered with a rich mycelial growth. Smooth seeds, such as rye-grass and meadow fescue, germinate, as a rule, without showing any mould. It is, however, the quality of the seed that is the influencing factor. Fresh, healthy, well-filled samples germinate without any trace of fungi appearing ; others, of the same kind but f r ~ ma different sample, become mouldy in a few days. Unless the seeds have quite lost their vitalityi the fungi do not really injure them or prevent the embryo sending out its rootlets, and clovers can grow when the outer coat is invisible owing to a thick crop of Ck&orniurn. My list of fungi is not exhaustive, as some forms, no doubt, have escaped observation ; but a varied and interesting - collection has already been made. The higher fungi are not largely represented ; there are no Basidiomycetes ; and, as yet, only three Ascomycetes have been noted. Two of these belong to Ck~tomium,a genus of Pyrenomycetes. They are saprophytic and superficiaI on whatever substance they grow. Ckmtornium finzeanum Zopf, which is perhaps the most frequently met with, has a small elliptical fruit crowned at the summit by a bristly head of olivebrown hairs, which are unbranched, wavy, and somewhat rough C. elaturn Kunze, which occurs also very frewhen mature. quently on the same kinds of seeds, is darker in colour, and the hairs of the crown are branched and very rough from the beginning. The ascospores of both species are a dull olive-brown. They grow on decaying vegetation, C. elaturn more especially on grass. In the germination case they grow on grasses and clovers, 'and occasionally on turnip seeds. There is no doubt that towards the end of each season, the laboratory must be well furnished with Ckdomium spores, and that may doubtless account for some of the infection. I have germinated 'some of the ascospores on a gelatine plate, and have obtained a beautiful growth of the Oidittm-like conidial form, a creeping mycelium with upright conidiophores bearing a terminal chain of conidia, but I have never detected any conidial growth on the seeds. T h e remaining Ascomycete, Gymnoascus Reesii Baran., I found on carrot and on turnip seed. It usually grows on decaying organic substances such as dung, and it is easy to understand how the spores might be blown by the wind on to the ripening
seeds. Gymnoascus is one of the less highly organised Ascomycetes, the peridium is composed of loose much-branched yellowish hyphz, which surround the fertile filaments. I4 sen mature, the walls of the small globose asci disappear, but the minute spores retain for a time the form of the ascus. The fungus was attached loosely to the spines of the carrot seed, and seemed to have little organic connection with it ; in this resembling the Ck~tomiunzs,which often grow on the awns of the grasses. Many of the smaller fungi grow with very little nutrition; those I have been watching often spread from the seeds to the germinating saucer, and grow vigorously on the porcelain, apparently on nothing, though doubtless some seed had lain on the spot and left some of its substance behind. T h e Hyphomycetes bulk very largely in this flora of seedfungi. The two ubiquitous species AspergilCus glaucw Link, and PenicilZium glaucum Link, appear continually. Cepkalosporium Acremonitmt Corda, Sporotrickum Caxum Nees, and Acremoniunz alternatum Link. are not infreauent. These all grow on decaying vegetation, and are very common moulds. Trickodermn viride Pers., the conidial form of Hypocrea rufa, I have found several times, and have cultivated it on a gelatine slide; there was a beautiful growth in three days of upright branching colourless conidiophores bearing the groups of b r ~ g h t green spores at the tips of the branches. A form of Sepedonium, plate IX. fig. I, entirely colourless, formed a white tuft on a grass seed. The spores, which are borne a t the tips of delicate hyphz, are globose and rather large, measuring about 18-zoFL in diameter. They have a thick eplspore, and are warced when mature. It agrees with the characters given of the species S. xylogenum Sacc., which has been found in Italy growing on wood. I have also to record in the Mucedinez a specimen of Botrytis Vera Fr., distinguished from other members of the genus by the lax branching of the sporophores. It grew on turnip seed. Among the Dematiez, Macrosporium commune Rabenh, the conidial form of Pleospora kerbarum, occurs most frequently. Helmintkosporium gramineum Rabenh. I have detected once on a grass seed. It is a parasite of cereals, destroying the leaves and so weakening the plant and injuring the grain. Some barley affected by it was sent into the laboratory during the summer of 1900. I have one record of Stackybotrys aCternans Bonord. It is a fairly common mould, and grows by preference on damp blotting paper. Stysanus stcmonites Corda, one of the Stilbez, by no means a rare fungus, has occurred several times on grass seeds. Fusarium roseum Link, which formed its delicate rose-tinted cushions on clover seed, is a member of the Tuberculariez. In
a culture I made, it grew in a very straggling fashion, and budded off a succession of spores from the tips of the branches. It has been recorded on decaying leaves and stems. Another species, F. cornmutaturn Sacc. (plate IX. fig. 2), is new to this country ; it falls under Saccardo's group "sporodockia laxa, effusa, byssina." On clover seed it hardly looked like a Fusarium, but on a culture plate it formed lax cushions; the spores are x 4-94. There is one three-septate and- measure 20-25 difference between this species and the type in that the sporophores are septate, otherwise Bonorden's drawing exactly represents the habit of the fungus, and " sporopkoris continuis" may not be a constant character. There are two forms of Hyphomycetes that have puzzled me a good deal. The first grew on a seed of Festzrca pratensis and from the character of the hyphz and spores I have placed it in the hitherto monotypic genus Langloisula of Ellis and Everhart. The hyphz are much larger, the spores also are larger, more deeply coloured, and not so pear-shaped as in the American species, L. spinosa. I therefore consider it to be a distinct species, and have named it. L. macrospora (plate IX. fi . 3). I fear the genus, however, rests on too narrow a foun ation of divergence from other forms, and the species might have been included in Acremoniella. The other specimen has baffled all my attem ts to place it under any recorded genus. It is in form and abit something like a Stemphylzzrm, and, but for lack of colour, I would have classed it under that genus. There is only one genus recorded under the group Mucedinez-hyalodictyeze, and it is entirely aifferent in form from the fungus I have been dealing with. I have been compelled to establish a new genus, which I have named Stemphyliopsis g. n., to connect it with its nearest ally among the Dematiez the species I have called keterospora, plate IX. fig. 4. The spores are exceedingly varied in form and size, and are borne at the tips of short branches from the main hyphz. They are warted when mature, and the whole plant remains colourless after some weeks' culture. I succeeded in reproducing it on a gelatine plate. I got the original specimens on turnip seed and on clover seed. The Mucorinez are the sole representatives of the Phycomycetes that have appeared in the germinating case, and Rkizopus nigricans Ehrenb. most frequently of all. It grows on any kind of seed, though on the whole it is partial to the grasses. It spreads very quickly, and in time extends over the whole available space. I have found another form also with rootlets somewhat similar to those of Rkisopus, which on that account I have included in the same genus. The sporangiophores rise singly from the runner-like hyphz, and near the top they form
2
e
an umbel of four short branchlets, each of which is terminated by a subglobose smooth sporangium. The tip of the branchlet expands gradually into the subglobose columella, to the base of which part of the sporangium wall remains attached after the dispersal of the spores. '.L'he whole plant is entirely colourless ; the spores are small, oblong, and blunt at the ends. From the mode of branching I have named it Rkizopu.~urnbellatus (plate IX. fig. 5). In one instance I found the main sporangiophore terminate in a sporangium with one side branchlet imperfectly developed; all the other examples have the umbellate head of branches. I have only found it once on clover seed, associated with another Jhcor. It is entirely microscopic, and I have not succeeded in cultivating it. The Mzrcor in which it was entangled, if indeed it was not parasitic on it, I have determined to be Mucor erectzss Bain. (plate IX. fig. 6). It forms delicate silky white tufts 2 or 3 centimetres in length. T h e hyphz branch frequently, and the very unequal branches terminate in a small yellowish sporangium. A distinctive feature of this species is the septum that is always present just above the point where the branch is given off. I found it on turnip and carrot seeds, and I got a further abundant growth on a mixture of gelatine and bean decoction. Mztcor erectus has been found in kurope on bread, plum decoction, and potatoes, but this is the first record for Britain. I have not yet been able to induce the growth of zygospores. M. racemosus Fres. (plate IX. fig. 7 ) appeared on clover seeds. I t is easily recognisable from the chlamydospores which are produced in great abundance on the hyphz and sporangiophores. I hardly think it is new to this country, but I cannot find any published record of its occurrence. It grows on a great variety of substances, and is very common on the Continent. EX1'1,AR'ATIOK OF PL-ITE IX." l'ig. I.-Sepedoniutn xylogenum Sacc. a, branches w i t h developing spores from a culture x 500. b, mature spores x 500. ,, 2.-Fusariutn co//rr/~tttat[rmSacc. a, sporophores w i t h developing spores x go. b, mature spores x 500. and spores x 500. ,, 3.-Langloisula macrospora sp. n. Fertile branches ,, 4.-Sfemphyliopsis hetcrospora g. et sp. n. Fertile hyphae and spores x 500. ,, 5.-RhLopus rr~rtbrIla/zrrsp. n. a, sporangiophore w i t h columellae x go. b, sporangium x 250. C , rootlets x 250. d , spores x 500. 6 . M u c o r ercctus Bain. a, sporangiophore x 250. b, columella x 500, spores x 500. ,, 7.-Mucor racemosus Fres. a, hyphae w i t h chlamydospores x 250. b, sporangium w i t h spores x 250. C , empty sporangium x 250. d , spores x 500. ,, 8.-itfuror spinosus V a n Tiegh. a, branching sporangiophore x go. b, columella and spores x 500. ,, 9.-SpheronemelZa oxysfora Sacc. a, pycnidia x 35. b, sporophores and spores x 500. "(By kind permission o f the Royal AIicroscopical Society).
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Plate 1X
FL L.S lel Rghley lith .
Hanhart imp
THE FUNGI O F GERMINATING FARM SEEDS. By A. Lorrain Smith. PLATE IX.
For the last two years I have been assisting in the botanical work undertaken for the members of the Royal Agricultural Society by the consulting botanist, and during that time I have had a .great deal to do with testing the germination of grasses, clovers, and other farm seeds. If the seeds are slow in germinating or unsound, they are liable to be attacked by various fungi, and it has been interesting to note the constantly recurring moulds. The saucers on which the seeds are germinated are thoroughly cleansed by immersion in strong acid solution, and by subequent washing and scrubbing. It is impossible in such
work absolutely to preclude fungoid infection from the surrounding atmosphere during the progress of germination; but all ordinary means are employed to secure cleanliness and speedy growth of the seeds ; and the evident conclusion is that the spores of most of the fungi that develop in the germination case have been brought into the laboratory with the samples. The rough pods of sainfoin carry most spores, and become very thickly covered with a rich mycelial growth. Smooth seeds, such as rye-grass and meadow fescue, germinate, as a rule, without showing any mould. It is, however, the quality of the seed that is the influencing factor. Fresh, healthy, well-filled samples germinate without any trace of fungi appearing ; others, of the same kind but f r ~ ma different sample, become mouldy in a few days. Unless the seeds have quite lost their vitalityi the fungi do not really injure them or prevent the embryo sending out its rootlets, and clovers can grow when the outer coat is invisible owing to a thick crop of Ck&orniurn. My list of fungi is not exhaustive, as some forms, no doubt, have escaped observation ; but a varied and interesting - collection has already been made. The higher fungi are not largely represented ; there are no Basidiomycetes ; and, as yet, only three Ascomycetes have been noted. Two of these belong to Ck~tomium,a genus of Pyrenomycetes. They are saprophytic and superficiaI on whatever substance they grow. Ckmtornium finzeanum Zopf, which is perhaps the most frequently met with, has a small elliptical fruit crowned at the summit by a bristly head of olivebrown hairs, which are unbranched, wavy, and somewhat rough C. elaturn Kunze, which occurs also very frewhen mature. quently on the same kinds of seeds, is darker in colour, and the hairs of the crown are branched and very rough from the beginning. The ascospores of both species are a dull olive-brown. They grow on decaying vegetation, C. elaturn more especially on grass. In the germination case they grow on grasses and clovers, 'and occasionally on turnip seeds. There is no doubt that towards the end of each season, the laboratory must be well furnished with Ckdomium spores, and that may doubtless account for some of the infection. I have germinated 'some of the ascospores on a gelatine plate, and have obtained a beautiful growth of the Oidittm-like conidial form, a creeping mycelium with upright conidiophores bearing a terminal chain of conidia, but I have never detected any conidial growth on the seeds. T h e remaining Ascomycete, Gymnoascus Reesii Baran., I found on carrot and on turnip seed. It usually grows on decaying organic substances such as dung, and it is easy to understand how the spores might be blown by the wind on to the ripening
seeds. Gymnoascus is one of the less highly organised Ascomycetes, the peridium is composed of loose much-branched yellowish hyphz, which surround the fertile filaments. I4 sen mature, the walls of the small globose asci disappear, but the minute spores retain for a time the form of the ascus. The fungus was attached loosely to the spines of the carrot seed, and seemed to have little organic connection with it ; in this resembling the Ck~tomiunzs,which often grow on the awns of the grasses. Many of the smaller fungi grow with very little nutrition; those I have been watching often spread from the seeds to the germinating saucer, and grow vigorously on the porcelain, apparently on nothing, though doubtless some seed had lain on the spot and left some of its substance behind. T h e Hyphomycetes bulk very largely in this flora of seedfungi. The two ubiquitous species AspergilCus glaucw Link, and PenicilZium glaucum Link, appear continually. Cepkalosporium Acremonitmt Corda, Sporotrickum Caxum Nees, and Acremoniunz alternatum Link. are not infreauent. These all grow on decaying vegetation, and are very common moulds. Trickodermn viride Pers., the conidial form of Hypocrea rufa, I have found several times, and have cultivated it on a gelatine slide; there was a beautiful growth in three days of upright branching colourless conidiophores bearing the groups of b r ~ g h t green spores at the tips of the branches. A form of Sepedonium, plate IX. fig. I, entirely colourless, formed a white tuft on a grass seed. The spores, which are borne a t the tips of delicate hyphz, are globose and rather large, measuring about 18-zoFL in diameter. They have a thick eplspore, and are warced when mature. It agrees with the characters given of the species S. xylogenum Sacc., which has been found in Italy growing on wood. I have also to record in the Mucedinez a specimen of Botrytis Vera Fr., distinguished from other members of the genus by the lax branching of the sporophores. It grew on turnip seed. Among the Dematiez, Macrosporium commune Rabenh, the conidial form of Pleospora kerbarum, occurs most frequently. Helmintkosporium gramineum Rabenh. I have detected once on a grass seed. It is a parasite of cereals, destroying the leaves and so weakening the plant and injuring the grain. Some barley affected by it was sent into the laboratory during the summer of 1900. I have one record of Stackybotrys aCternans Bonord. It is a fairly common mould, and grows by preference on damp blotting paper. Stysanus stcmonites Corda, one of the Stilbez, by no means a rare fungus, has occurred several times on grass seeds. Fusarium roseum Link, which formed its delicate rose-tinted cushions on clover seed, is a member of the Tuberculariez. In
a culture I made, it grew in a very straggling fashion, and budded off a succession of spores from the tips of the branches. It has been recorded on decaying leaves and stems. Another species, F. cornmutaturn Sacc. (plate IX. fig. 2), is new to this country ; it falls under Saccardo's group "sporodockia laxa, effusa, byssina." On clover seed it hardly looked like a Fusarium, but on a culture plate it formed lax cushions; the spores are x 4-94. There is one three-septate and- measure 20-25 difference between this species and the type in that the sporophores are septate, otherwise Bonorden's drawing exactly represents the habit of the fungus, and " sporopkoris continuis" may not be a constant character. There are two forms of Hyphomycetes that have puzzled me a good deal. The first grew on a seed of Festzrca pratensis and from the character of the hyphz and spores I have placed it in the hitherto monotypic genus Langloisula of Ellis and Everhart. The hyphz are much larger, the spores also are larger, more deeply coloured, and not so pear-shaped as in the American species, L. spinosa. I therefore consider it to be a distinct species, and have named it. L. macrospora (plate IX. fi . 3). I fear the genus, however, rests on too narrow a foun ation of divergence from other forms, and the species might have been included in Acremoniella. The other specimen has baffled all my attem ts to place it under any recorded genus. It is in form and abit something like a Stemphylzzrm, and, but for lack of colour, I would have classed it under that genus. There is only one genus recorded under the group Mucedinez-hyalodictyeze, and it is entirely aifferent in form from the fungus I have been dealing with. I have been compelled to establish a new genus, which I have named Stemphyliopsis g. n., to connect it with its nearest ally among the Dematiez the species I have called keterospora, plate IX. fig. 4. The spores are exceedingly varied in form and size, and are borne at the tips of short branches from the main hyphz. They are warted when mature, and the whole plant remains colourless after some weeks' culture. I succeeded in reproducing it on a gelatine plate. I got the original specimens on turnip seed and on clover seed. The Mucorinez are the sole representatives of the Phycomycetes that have appeared in the germinating case, and Rkizopus nigricans Ehrenb. most frequently of all. It grows on any kind of seed, though on the whole it is partial to the grasses. It spreads very quickly, and in time extends over the whole available space. I have found another form also with rootlets somewhat similar to those of Rkisopus, which on that account I have included in the same genus. The sporangiophores rise singly from the runner-like hyphz, and near the top they form
2
e
an umbel of four short branchlets, each of which is terminated by a subglobose smooth sporangium. The tip of the branchlet expands gradually into the subglobose columella, to the base of which part of the sporangium wall remains attached after the dispersal of the spores. '.L'he whole plant is entirely colourless ; the spores are small, oblong, and blunt at the ends. From the mode of branching I have named it Rkizopu.~urnbellatus (plate IX. fig. 5). In one instance I found the main sporangiophore terminate in a sporangium with one side branchlet imperfectly developed; all the other examples have the umbellate head of branches. I have only found it once on clover seed, associated with another Jhcor. It is entirely microscopic, and I have not succeeded in cultivating it. The Mzrcor in which it was entangled, if indeed it was not parasitic on it, I have determined to be Mucor erectzss Bain. (plate IX. fig. 6). It forms delicate silky white tufts 2 or 3 centimetres in length. T h e hyphz branch frequently, and the very unequal branches terminate in a small yellowish sporangium. A distinctive feature of this species is the septum that is always present just above the point where the branch is given off. I found it on turnip and carrot seeds, and I got a further abundant growth on a mixture of gelatine and bean decoction. Mztcor erectus has been found in kurope on bread, plum decoction, and potatoes, but this is the first record for Britain. I have not yet been able to induce the growth of zygospores. M. racemosus Fres. (plate IX. fig. 7 ) appeared on clover seeds. I t is easily recognisable from the chlamydospores which are produced in great abundance on the hyphz and sporangiophores. I hardly think it is new to this country, but I cannot find any published record of its occurrence. It grows on a great variety of substances, and is very common on the Continent. EX1'1,AR'ATIOK OF PL-ITE IX." l'ig. I.-Sepedoniutn xylogenum Sacc. a, branches w i t h developing spores from a culture x 500. b, mature spores x 500. ,, 2.-Fusariutn co//rr/~tttat[rmSacc. a, sporophores w i t h developing spores x go. b, mature spores x 500. and spores x 500. ,, 3.-Langloisula macrospora sp. n. Fertile branches ,, 4.-Sfemphyliopsis hetcrospora g. et sp. n. Fertile hyphae and spores x 500. ,, 5.-RhLopus rr~rtbrIla/zrrsp. n. a, sporangiophore w i t h columellae x go. b, sporangium x 250. C , rootlets x 250. d , spores x 500. 6 . M u c o r ercctus Bain. a, sporangiophore x 250. b, columella x 500, spores x 500. ,, 7.-Mucor racemosus Fres. a, hyphae w i t h chlamydospores x 250. b, sporangium w i t h spores x 250. C , empty sporangium x 250. d , spores x 500. ,, 8.-itfuror spinosus V a n Tiegh. a, branching sporangiophore x go. b, columella and spores x 500. ,, 9.-SpheronemelZa oxysfora Sacc. a, pycnidia x 35. b, sporophores and spores x 500. "(By kind permission o f the Royal AIicroscopical Society).
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Plate 1X
FL L.S lel Rghley lith .
Hanhart imp