Visit to the British Museum

Visit to the British Museum

VISIT TO THE BRITISH MUSEUM. 365 ing, that led to the discovery of the animal. At some considerable trouble and expense, he brought a specimen to Sy...

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VISIT TO THE BRITISH MUSEUM.

365

ing, that led to the discovery of the animal. At some considerable trouble and expense, he brought a specimen to Sydney, which Mr. Krein at once pronounced to be a Ceratodus. Finally, Dr. Gunther directed the attention of the Members of the Association to the remarkable fact that the geographical distribution of the Dipnous Ganoids closely coincides with that of a Teleosteous family, viz., the Osteoglossidse j the Ganoid Protopterus being accompanied by the Teleosteous Heterotis, in tropical Africa j Lepidosiren, by Sudis, in tropical America; and Ceratodus, by Osteoqloesum Leichardti, in tropical Australia, therefore he could not hesitate to predict that a dipnous fish, probably closely allied to Ceratodus, would, before long, be discovered in Borneo, an island in which Osteoqlossum j01'11WSUm is of common occurrence. VISIT TO THE BRITISH MUSEUM. BOTANICAL DEPARTMENT. MARCH 23RD, 1878. Director-W. CARRUTHERS, ESQ., F.R.S., Keeper of the

Department. (Report by G. S.

BOULGER,

EsQ.., F.L.S., F.G.S.)

Some twenty or thirty Members assembled in the private inner rooms of the Department, where the Director explained the history and arrangement of the herbaria under his charge. The arrangement followed is that of De Candolle's Prodromus, only the British and Sloane collections being kept apart-all others are gradually distributed into the general herbarium. No poisoning is used to keep off insects, but the plants when once thoroughly dried, are placed in well-fitting cahinets, in which are large pieces of camphor. The Keeper said that, after twenty years' experience, he found that very few plants suffered from the depredations of insects, except some of the Leguminosre. The collection of Sir Hans Sloane, purchased by the nation rather more than a century ago, is comprised in 300 volumes. It was commenced by Sloane when he was a surgeon in Jamaica, many of his plants being figured in his History of Jamaica. He also obtained many other collections, including that of Krempfer,

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VISIT TO THE BOTAYI CAL DEPARTMENT

a missionary from Japan, and the very valuable collection made by Buddle, and us ed by Dillenius ill preparing th e third edition of Ray's Synopsis. Th ese herbaria were shown to the :Members, as also was that made by Ray, obtained about fifty years ago from th e Apoth ecaries' Company. Mr. Carruthers remarked that Ray's system of classification, being a natural one, his position was higher now than during the last century, when Linnseus' artificial method prevailed. The original drawings made by James Sowerby, for" English Botany," with Sir J. E. Smith's notes, were next shown. These are preserved in the book-boxes, known as "Solanders," aft er their inventor, Dr. Selander. They were first used by Sir -Ioseph Banks in his trav els with Captain Cook, and those used by Robert Brown in Australia were also exhibited. The marvellous drawings of the two brothers, Francis and Ferdinand Bauer, who were supported and pensioned by Sir Jo seph Banks, were also examined. These include a series illustrating the development and anatomy of wheat and another of plant diseases, by Francis, who lived at K ew, and one of Australian plants, by F erdinand, who accompanied Brown. Mr. Carruthers informed the visitors that he had revived Bauer's specimens of the minute annelid, Vibrio, known as the paste-eel, after it had been desiccated or "pectously dead" for sixty years. The true nature of " ergot," which is the " sclerotia," or modified mycelial thallus of a fungus known as Clavicep s, correctly drawn by Bauer, though not understood till about twenty years ago, was also explained, and attention called to the drawings of fungi by Sowerby and Mrs, Russell, and those by Mr. W orthington Smith, illustrating his views of the Potato Disease (Phytophthora infestans.) The company then proceeded to the public gall ery, where Mr. Carruthers gave an account of the whole Vegetabl e Kingdom, from the geologists' point of view. For them, he said, th e best division of plants was into " Oellular" and" Vascular ." 'Vater and air destroyed nearly all cellular plants, the fossils called Algee, from palseozoic rocks, not being so in fact. With the exception of some parasitic fungi fonnd in the stems of Lepidodendroid trees from the CoalMeasures , we know of no cellular plants till we come to a true alga in the Tertiaries. The Vascular Cryptogams (Ferns, Club-mosses and Horsetails) , occur in rocks of every age, from the Devonian upwards, and have remained most remarkably unchanged through-

OF THE BRITI SH MUSEUM.

367

out th eir history ; th e well-known fern from th e Devonian of Ireland being almost identical with th e existing F ilmy-fern (Hymenophyll um). Lycopods were far more highl y organised and far larger in stem, foliage and fruit in Palreozoic times th an now ; th ey are, in fact, poorly represented in Secondary and Tertiary t imes ; so also th e Calamit es seem high er than our recent E quiset um ; but the spore s ofthese g iant t rees of Carb oniferous times ar e exactly similar in size and struct ure to th ose ofthe herbs which now represent th em, Geologically and botanicall y th e Gymnosperms come between the Club-mosses and th e Fl owering- plants or Angiosperms, and attention was particularly called to Cycads, represent ed by fossils from Sussex, P ortl and and the I sle of Wight, and by the recent genera Cycas, from the Old WorId, Z amia from the New, Ceratozamia from Mexico, Macrosomia from Au stralia, and Dion, a remarkable American genus with stalked anth eriferous scales resembling those of th e spike of Equisetum. A sub-t ribe of Cycadere, with berry-l ike fruit, exists only in a fossil sta te. Am ong t he Ooniferre, sections of the stem of the Cedar of Lebanon and of th e Sequoia or W ellingtonia, a genus which grew ill England in Gault and Tertiary times, but is now confined to California, were pointed out ; whilst Monocotyledonous specimens, from t he Tertiary beds of Antigua, were exhibited as showing rapid silicification, even the leaf-buds being preserved. The Pan danacere or Screw-pines occur in the Oolite, and the Nipadites of th e L ondon Clay of Sheppey belong s to this Order. The P alms only appear in Tertiary times ; both types, tha t with pinnate and th at with palmat e leaves, occurring in the Bourn emouth beds. Noticing in passing the case cont aining th e curious parasites, Mistlet oe, Raffiesia and Balanophora, the Director concluded by calling attention to two tabl e-cases, one exhibiting various phases of fossilization, th e filling in of dead or decaying organ ic ti ssues with lime or silica, th e slow combustion of wood, passing into ligni te, j et and coal, and the similar effects pr oduced by rapid combustion under pres sure, exemplified in specimens from the Tooley-str eet fire; the oth er conveying a caution again st determinations of fossil plants on the evidence of leaves alone, in the great variability of foliage in the genera Hakea and Banksia, belonging to the Ord er named in this account Prot eacece, an Order abundantly represented in our Bourn emouth and Isle of Wight Tertiaries, but now mainly Australian.