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than protective appliances. Every particle of the shell has been held in suspension or solution in the body of the living animal; and there is not even a microscopic character in the shell which has not its corresponding peculiarity in the animal. It is very much to be doubted whether, in all cases, the morphology of the soft parts affords better indications of blood relationship than that of the hard parts. Mr. Marrat has pointed out that, fairly within the pale of the group known as Nasse, there are important differences in the animals.*

It is desirable not to underrate the value of distinctions which are practically accessible. With unlimited powers of observation, the soft parts would be our safest guide, but we have not such powers. Moreover, Nature, not without imitators, in certain cases takes a deal of pains with her externals, bestowing on them superlative but useless beauty in sculpture or in colour. It is frequently thus with shells. Colouring that an artist might envy is covered up in a sheath of felted epidermis, and never seen during the life of the animal. Now, where Nature makes an apparently useless character prominent, it becomes also significant. It may reveal affinities as reliably as does any other part of the science of morphology.

The hidden loveliness of shells seems to show that all the phenomena of biological development are not to be accounted for on the principle of natural selection, or the law of advantage, an admission to which, I believe, Mr. Darwin himself is increasingly inclined to attach importance.

A lepidopterist, taught to discard distinctions of colour in examining the Butterflies and Moths, might as well forego his work altogether. No doubt, if we could only go deep enough, every portion of a living organism implies every other portion ; but such a diagnosis is not for the present generation. One word, lest Professor Semper's admirable researches should be deemed to have met with scant appreciation. As a penetrating observer of Nature, Professor Semper ranks very high. His strictures fall heaviest upon the geologists who know but little by examination of the soft parts of the fossil shells which fill their magnificent cabinets. But the geologists are a puissant race, and are in little need of a defender, whether they use the pen or the hammer. These fine shells from Tanganyika are not, I think, tonguetied, because, so far as I know, the animals have not been critically examined in a living state.

* See Society's Proceedings, vol. xxxiv., 1879–80, Appen. pp. 17–20.

My waning space reminds me that I must bring this short notice to a close.

What are these hitherto unseen forms, and whence came they? Twenty years ago no intelligent eye had ever received the image of such objects. They come as if from another world, and yet they are not entire strangers. The waters which supply Niagara, and those of the great Siberian lakes, cast on their shores forms too similar not to belong to relatives. With my own hands I have taken from the Sea of Galilee, and from the bright stream that rushes from the fountain of Elisha, near to Jericho, shells resembling those of Lake Tanganyika. Once it was suggested that the valley of the Jordan, the Red Sea—then closed at the southern end and filled with fresh-water-the valley of the Upper Nile, and the great African lakes, formed portions of one vast freshwater lake system in Eocene times. I lay no stress on this conjecture, but my friend Mr. Moore tells me that Dr. Gunther * has shown that the fishes of the Jordan, and those of the Upper Nile, have apparently some affinity.

All the seven species are what is termed new to science,

See Introduction to the Study of Fishes, by Dr. Gunther. A. and C. Black, 1880, pp. 227.-See article “ Ichthyology,” Encyclopedia Britannica, vol. xii., 1881, p. 672, by the same; as also Appendix C on the “Fishes of the Nile,;' in Petherick’s Travels in Central Africa. London, 1869. 8vo.T. J. MOOBE.

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and all have gills for breathing the air contained in the water. Tiphobia horei is certainly like nothing in the earth or in the waters under the earth : that it has no proper epidermis shows, I think, that the waters of the lake must be very pure from any kind of free acid. Neothauma tanganyicense is like a Paludina, but its size and lengthened anterior canal remind one of shells from North America. Limnotrochus Kirki is the greatest gem of all. It seems to mimic Echinella, a marine littoral form, and figuratively is miles away from any known fresh-water species. Melania horei is a world-wide form, selected because it is so like a shell I found in the Fountain of Elisha. Paramelania damonis is a beautiful shell, quite marine in its aspect. Melania admirabilis, has been so called, I suppose, because, being a vegetable feeder, it looks so like an animal feeder. Lastly, Melania nassa is, if I may so say, absurdly like some well-known forms of Nassa, sea-shells and animal feeders. Not a true air-breathing fresh-water species, like our pond-snails, was in the list, though plenty of true air-breathing land-shells were found on the shores of the lake.

How strange this tendency to the imitation of marine forms, in the very heart of Africa! Are they vestiges of a time when Africa was submerged, and sharks and whales swam over the spot where Ujiji now stands; and, as the land rose, and the waters drained away, did the ancient seashells, the Nassæ and Littorinæ, accommodate themselves to less and less of salt in their surrounding element, the former of these, moreover, adopting a vegetable diet; the animals losing their long necks, and their shells becoming rounded in front? If so, we have mollusca placed in one genus, which, in their pedigree, were wide asunder-a converging instead of a diverging pedigree ! But, in this case, what becomes of the dogma of monophyletic descent ? suppose

that these wonderful shells are the representatives of

Or we may

ages of evolution on the spot; dating from the time when, as Haeckel asserts, the first mollusc was derived from a worm with a body cavity. A single case of fortuitous pseudomimicry is conceivable, but the probabilities against it mount up, in a geometric ratio, with every additional distinct point of resemblance. And when several examples occur together, to believe such quasi-mimicry to be the result of chance must be, in a scholastic aspect, very meritorious. It seems to myself that the path of least resistance in which, as some say, we are all compelled to travel, leads to the conclusion that some of these shells from Tanganyika are descended from marine progenitors.

The Rev. H. H. HIGGINS exhibited and made remarks upon some specimens of Pentacrinus or Sea Lily, recently added to the Free Museum. They were sent, with various Corallines, Cirripeds, Sponges, etc., at the suggestion of Dr. Martin Duncan, F.R.S., by Mr. Alleyne S. Archer, of Barbadoes, through the kind offices of Sir T. Graham Briggs, Bart., Member of H.M. Council and of the Federal Council of the Leeward Islands. Dr. Hicks read a paper on “ The Development of the

HICKS Sea Hare."

Mr. T. J. MOORE exhibited a group of specimens of the Coney of Scripture, Hyrax siriacus, and their skulls, specially collected for the Liverpool Free Public Museum by Mr.H.Heywood Jones during a visit to Palestine in the spring of 1881.

Mr. MOORE also exhibited sketches of a specimen, twenty feet long, of a Xiphioid Whale, Hyperoodon Butzkopf (H. rostratus), captured Sept. 2, 1881, on the Lancashire side of the river Mersey, near Speke, the skeleton of which had been secured for the Liverpool Museum. This makes the fourth capture of this species in the Liverpool district ; three others being recorded by Mr. Byerley, in his Fauna of Liverpool, 1854, p. 9.

Some rare plants from the Botanic Gardens were exhibited by Mr. RICHARDSON, the Curator.

SECOND ORDINARY MEETING,

ROYAL INSTITUTION, October 31st, 1881. EDWARD DAVIES, F.C.S., F.I.C., PRESIDENT, in the

Chair.

Dr. R. Williams, Professor G. H. Rendall, M.A., Principal of University College, Professor Oliver J. Lodge, D.Sc., of University College, and Messrs. A. T. Smith, E. Mount, and J. W. Rennie were elected Ordinary Members.

Mr. WALTHEW exhibited a Japanese educational work, containing actual specimens of various kinds of woods attached to each page, the names, in Japanese and European characters, being appended to each specimen.

Mr. Josiah MARPLES then read a paper, entitled, “Some Notes on the last months in the Life of Mary Queen of Scots, hitherto unpublished in England."*

THIRD ORDINARY MEETING.

ROYAL INSTITUTION, November 14th, 1881. EDWARD DAVIES, F.C.S., F.I.C., PRESIDENT, in the

Chair. Messrs. R. J. Lloyd, B.A., and G. Eyre Evans, and the Rev. S. Fletcher Williams were elected Ordinary Members.

The Rev. HENRY H. HIGGINS said that all the members of the Society would be gratified to hear that one of their VicePresidents, Dr. Campbell Brown, was, on Nov. 12th, elected to the Professorial Chair of Chemistry in University College, Liverpool. Mr. HIGGINS exhibited some implements supposed to have

. See page 25.

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