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That gigantic elk, Megaceros Hibernicus, has been found abundantly in the peat bogs of Ireland and the Isle of Man, also in Lancashire* along with remains of Hippopotamus major. Bos longifrons, though now extinct, we know for certain was co-existent with the earliest human inhabitants of these isles.

At a time like the present when a disposition to rush into extreme views respecting the antiquity of our race is so constantly manifested amongst us, it is well to bear in mind such facts as these, for I cannot help thinking they counteract in some measure the revolutionizing tendency of the evidence we have been principally considering here. The whole question however, it appears to me, is in such a peculiarly delicate position at present, that to attempt to arrive at any definite conclusions respecting it, is well nigh impossible. The wiser course by far is to exercise that habit of mind which a reviewer of Mr. Darwin's work on the "Origin of Species" has recommended to all students of the hypothesis set forth there,t-the "thätige skepsis" of Goethe-doubt which so loves truth that it neither dares rest in doubting, nor extinguish itself by unjustified belief.

The second Paper was then read,

ON THE HEPATICS AND LICHENS OF THE

NEIGHBOURHOOD OF LIVERPOOL.

BY FREDERICK P. MARRAT.

(See Appendix.)

• Owen's "British Fossil Mammals and Birds," p. 467.

+ "Times," 26th December, 1859.

At p. 171, last line, for 1860 read 1800; at p. 174, line 21, for on, read ou; and in note for of their objects: read of these objects:

TWELFTH ORDINARY MEETING.

ROYAL INSTITUTION, 19th March, 1860.

The Rev. H. H. HIGGINS, M.A., President, in the Chair

It was communicated from the Council that they deemed it desirable to mark their appreciation of Mr. GRINDON's Flora of Manchester, by presenting to the author through the President of the Medical School in that city, a bound copy of the monographs on the local Flora of this district, extracted from the Proceedings of the Society; and a Sub-Committee was appointed to carry out this recommendation, consisting of the Rev. H. H. Higgins, M.A., President, D. P. Thomson, M.D., Hon. Secretary, and C. Collingwood, M.B., Lecturer on Botany.

The CHAIRMAN exhibited a copy of a work lately added to the Free Public Library-a fac-simile of "The Game of Chesse, by William Caxton," reproduced from a copy in the British Museum, printed in black letter, with many curious engravings. He observed that it was the second book ever printed in England, and was executed by Caxton in 1474. It was a remarkably interesting work, detailing the origin of the game of chess, which it attributed to Evil Merodach, King of Babylon. He detailed the peculiarity of the pawns and other features of the game as played by the ancients, contrasting them with those obtaining at the present day.

Mr. NISBET drew attention to a splendid meteor observed by him on Saturday week as he was crossing the river to Egremont, and seen also at Drogheda.

Mr. MOORE, curator of the Derby Museum, read a list of captures chiefly made at Hilbre during the late low tides. The list comprised above thirty species, besides microscopic specimens. The most remarkable was a small crab, Pilumnus hirtellus, which, it was stated, had not been obtained before in

the district of Liverpool. He also exhibited two young living alligators, sufficiently small to be kept in an ordinary aquarium.

Professor ARCHER exhibited specimens of paper manufactured from sea wrack, Zostera marina, by Mr. H. Spooner, of Newark-upon-Trent, Nottinghamshire. From the experiments made by Mr. Spooner, and the results obtained, there appears to be no doubt that this abundant material will not only answer the purpose of the paper maker, but is remarkably well adapted for those kinds required for the finer descriptions of engraving, printing, &c., the fibre being fine, tough, exceedingly elastic, and admitting of complete bleaching.

Mr. BYERLEY, F.L.S., showed a specimen of the common frog enormously distended by air.

Dr. NEVINS gave an account of a large brood of salamanders. The remarkable circumstance connected with the case was the proof it afforded of the length of time the ova had been carried, which would not be less than three months. The following Paper was then read

ON HOMOMORPHISM;

OR, ORGANIC REPRESENTATIVE FORM.

BY C. COLLINGWOOD, M.B., F.L.S., &c.

BY Homomorphism is meant the recurrence of certain external forms in various departments of Nature, more or less widely separated by internal structure; so that at the outset, it is necessary to divest the mind of the idea that it partakes in any way of the character of homology.

By Homology, indeed, is distinctly understood a structural affinity, uniting, as it were in a common bond, the same organ, under whatever form it may appear, or whatever function it may assume. The limbs, for example, of quadrupeds, the wings of birds, and the fins of fishes, are thus structurally

united, and although taking very different forms, are strictly homologous one of the other. But the wing of a butterfly, though bearing a general analogical resemblance to that of a bird, has yet no community of structure with it; nor has the wing of a bat any stronger claim to be considered homologous with the wing of a true bird. The wings of a bat, or a butterfly, are homomorphous with the wings of a bird, and indeed perform the same function;-so far, therefore, they may be regarded as analogues of those organs. But it must also be understood that homomorphism does not necessarily imply analogy, in the proper sense of that term; for by analogy is understood, as distinguished from homology, an agreement of fuuction, where there is no community of structure, as just instanced; whereas homomorphism, while it expresses, primâ facie, an absence of agreement in structure, or homology, may, or may not, be accompanied by similarity of function, though the want of such functional agreement is the rule, and its presence an accidental exception.

From this it will readily appear that the study of homomorphism cannot be expected to be so prolific of important results as the study of homologies, inasmuch as these latter are believed to be the bonds of connection which unite forms apparently widely separated, and which throw light upon the true affinities of obscurely constituted organisms. And herein probably lies the reason why homomorphism has attracted so little attention from naturalists. I am not aware of any essay (though such there may be) upon this curious subject, which either collects and compares the various examples with which Nature abounds,-or, still less, which attempts to treat it upon such a basis as that on which all natural science should be treated. It appears indeed to be barely referred to here and there in the writings of zoologists, as something striking and remarkable, usually called up by some peculiarly curious fact in connection with the special subject upon which they

happen to be engaged, and then quickly dismissed as a barren topic, unworthy of further investigation. A singular resemblance thrusts itself upon the attention, claims a passing allusion, and is no more thought of. My object, therefore, in the present paper, is to dwell more at length upon the vast number of recurrent forms met with in the animal kingdom, referring to the considerations which seem to be derivable from them, and the generalizations which appear to be legitimately deducible from the enquiry.

It will probably occur to some, at the first blush, that organic homomorphism has a correlative in the inorganic world; but the restricted definition already given will exclude the class of representative forms known to the chemist under the name of isomorphous. This term refers to a similarity of crystalline form, assumed by substances (even compounds) of different constitution, a strong corroborative argument in favour of Wollaston's theory of the simple form of atoms.* But Mitscherlich has shown that isomorphism implies, primâ facie, in bodies subject to it, a certain agreement of chemical properties, which may be regarded as the analogues of organic functions. Thus, "the acids of arsenic and phosphorus form salts which crystallize alike, and their respective bases not only correspond in a more general way in acquiring acid properties with oxygen,-forming gaseous compounds with hydrogen, &c., but also in the unusual proportions in which oxygen and hydrogen enter into union with them,-while the corresponding arseniates and phosphates also agree in taste, and in the degree of force with which they retain their water of crystallization." This similarity of properties therefore raises isomorphous bodies from being homomorphs to the dignity of analogues.

The animal kingdom has been so severely scrutinized during the last half century by men of keen perception, such Bakerian Lecture, 1813.

+ Daubeny, Atomic Theory, p. 170.

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