April, 190b.] 



KNOWLEDGE. 



73 



piUSTRATED MAGAZ1NE| 



Founded by RICHARD A. PROCTOR. 



Vol. XXVI.] LONDON : APRIL, 1903. 



[No. 210. 



CONTENTS. 



The Palaeontological Case for Evolution. By R. 



LVDEKKEB 



Lord Kelvin s Nev^ Idea about Ether Atoms. By Dr. 



.J. G-. McPhEHSON, F.R.S.E. .. 



Cross-Fertilisation in Sociology.^ll. By .T. Colliek... 



The Chemistry of the Stars. II. — Varieties of Spectra. 



r.y A. FoWLEU, F.it.A.!>. (Illiixtrafed) 



Photograph of the Nebula round the Star DM. No. 



980, Zone 34', in the Constellation Auriga. By 



Isaac Bobp:rts, d.sc, f.b.s. (Plate) 

 Man s Place in the Universe. By E. Walter MArxDER, 



F.B.A.S. ... 



Letters : 



The Yisibimty of tbk Ceescent of Venus. By W. T. 

 Mackie. Note by J. N. Strassmaiee, s.j. 



The Ceoss of S. Sophia. By F. C. Buekitt. Note by 

 E. M. Anioniadi ..' "^ 



British Ornithological Notes. Conducted by Haeet F. 



WiTHERBT, F.Z.8., M.B.O.U 



Notes 



Notices of Books 



Books Received 

 St. Sophia, Constantinople.— III. By E. M. Antomadi, 



F.R.A.s. (Illustrated) 



Microscopy. Conducted by M. I. Ceoss 



Notes on Comets and Meteors. By W. F. Bbnning, 



F.R.A.s ' ' 



The Face of the Sky for April. By W. 



Shackleton, F.E.A.S. {Illustrated) 



Chess Column. By C. D. Locock, b.a 



THE 



PALAEONTOLOGICAL 

 EVOLUTION. 



By R. Lydekker. 



CASE FOR 



At the date of publication of the first eilition of " The 

 Origin of Species," in 1859, the poverty of our palieouto- 

 lof^ical collections— especially as regards the remains of 

 vertebrates — the so-called " imperfection of the geological 

 record," and the comparatively small area of the earth's 

 surface which had been geologically examined, were 

 regarded as reasons sufficient to explain the absence of 

 evidence of any one definite line of descent of a modern 

 from an ancient type of animal. In addition to this, it 

 was pointed out that a very large percentage of the fossil 

 vertebrates then known to science were represented by 

 sucli fragmentary remains that it was almost, if not 

 absolutely, inii.ossilile to arrive at any satisfactory estimate 

 of their real iillinities and relationships; and it seems to 

 have been taken for granted that tliere was coin})aratively 

 little hope of matters l)eiug materially mended in tliese 

 respects in the near future. Moreover!^ the suggestion was 



hazarded* that one living mammal might be the descendant 

 of a second, and that possibly the horse might trace Lack 

 its ancestry to the tapir. Not a shadow of suspicion 

 seems indeed to have existed at that time in regard to the 

 ancestry of the horse (or, as we should properly say, the 

 horse tribe), although, curiously enough, the chief stages 

 in tliat line of evolution were already known to science. 



Matters remained in much the same state till at least as 

 late as the issue of the fifth edition of " The Origin of 

 Species " in 1869. Twenty years later, however, when 

 another important work on the same subject — Dr. A. R. 

 Wallace's " Darwinism " — made its appearance, evolu- 

 tionists were able to bring forward a much more formidable 

 array of evidence in favour of their doctrine, especially in 

 regard to vertebrates. During the two decades which had 

 elapsed since the publication of the fifth edition of 

 Darwin's great work, the marvellous discoveries in verte- 

 brate palaeontology made by Marsh and others in the 

 north-western territories of the United States had come as 

 a revelation to the zoological world ; while the enormous 

 number of mammalian remains brought to light during 

 the working for commercial purposes of the valuable 

 deposits of phosphorites in Central France had served to 

 revolutionize our conceptions of the extent and relation- 

 ships of the ancient Tertiary mammalian fauna of Europe. 

 Marsh, ably seconded in this country by Huxley, had also 

 been enabled to work out in detail the ancestry of the 

 modern horse and its relatives (though tlie identity of the 

 earliest member of the series with the little hyracothere 

 discovered more than forty years previously in the London 

 Clay was still unsuspected) ; and the descent of the modern 

 rhinoceroses from primitive types of odd-toed mammals 

 had likewise been demonstrated. Huxley, too, had made 

 known the existence of many remarkable resemblances 

 between the skeletons of birds and those of the extinct 

 dinosaurian reptiles ; while his account of the relationships 

 of the ancient to the modern crocodiles afforded an im- 

 portant piece of evidence in favour of the evolution of 

 animal forms. 



It was still, however, a matter of reproach to those who 

 supported the doctrine of evolution that so few phylogenies, 

 or lines of descent, could be cited as firmly established on 

 palasontological evidence. Huxley had indeed insisted 

 (perhaps with rather too much emphasis) on the intimate 

 relationship formei-ly existing between birds and reptiles 

 on the one hand, and between salamanders and fishes on 

 the other, but practically nothing liad been learnt with 

 regard to the affinities between mammals and other groups 

 of the vertebrate stock. Again, the modern type of bony 

 fishes were believed to have made their appearance 

 suddenly in the Cretaceous epoch, and to have no connec- 

 tion with the earlier mail-clad fishes commonly called 

 ganoids ; although, it is true, the suggestion occurs in Dr. 

 Wallace's book that certain reputed members of tlie 

 latter group might prove to be much more closely related 

 to the bony fishes than was commonly considered to be 

 the case. 



Since 1889 our knowledge of the mutual relationships 

 of different groups of vertebrates, and of the phylogeny of 

 particular families, as deduced from their fossil remains, 

 has increased by leaps and bounds And, so far as the 

 specimens in our museums are concerned, we are now 

 siirt'enng from an enibarras des richesses rather than from 

 lack of material. 



So far as we are aware, no attempt has been made of 

 late years to lay before the general public in a popular 

 manner some of the most striking features of the case for 

 evolution as presented by palieontological evidence. 



See Fifth edition, page 347. 



