THE PALEONTOLOGIC RECORD 3°95 
if not the first, to bring the fruits of paleontology to the support of 
evolution. But Leidy, as far as a hasty search through his writings 
could reveal, nowhere expressly advocated the doctrine of recapitula- 
tion. Indeed, he gave but little attention to the philosophical bearings 
of paleontology, generally partly because of temperament and partly 
because in those pioneer days material to serve as a basis for generaliza- 
tion was still scanty. 
Gaudry, one of the first European paleontologists to champion the 
cause of evolution,? likewise did not specially advocate the doctrine 
of recapitulation. An examination of his “Philosophie Paleontolo- 
gique” fails to reveal any definite belief in this doctrine. 
Huxley, as far as I can gather from his papers and essays, be- 
lieved in this doctrine, though with certain implied reservations as to its 
general applicability. In his presidential address to the Geological 
Society of London on “ Paleontology and the Doctrine of Evolution ” 
delivered in 1870, we find some interesting comment on the signifi- 
cance of the splints of the living horse, which he regards as indicative 
of the presence of three complete digits in the horse ancestor. But 
Huxley was never an out-and-out advocate of the biogenetic law. 
Cope and Marsh, as we all know, were staunch upholders of evolu- 
tion; and Cope, at least, was also a staunch upholder of the doctrine of 
recapitulation. In his “Primary Factors of Organic Evolution,” his 
last contribution to philosophical paleontology, he devotes considerable 
space to proving this doctrine. He says: . 
The representatives of each class passed through the stages which are 
permanent in the classes below them in the series. 
And he backs up this proposition with evidence derived from the 
ontogeny and phylogeny of batrachia, the antlers of deer and the blood 
trunks of vertebrates generally. For all that, Cope recognized the 
justice of certain criticisms which had been brought against the doc- 
trine of recapitulation and urged caution in its application. 
An example or two of recapitulation may now be cited from the 
field of the lower vertebrates. 
The mode of development of the teeth in Neoceratodus has some- 
times been adduced as an illustration of recapitulation. It is well 
known that the Devonic dipnoans (e. g., Dipterus) had teeth com- 
posed of rows of denticles, those in each row being more or less fused 
at their bases. During the history of the dipnoans since the Devonic 
period, the separate denticles have merged more and more until in 
Ceratodus and the living Neoceratodus, the rows of denticles are, in 
* According to a letter from Darwin to Gaudry dated January 21, 1868. 
“The Life and Letters of Charles Darwin,” edited by his son Francis Darwin, 
New York, 1899, Vol. II., p. 269. 
*“ Primary Factors of Organic Evolution,” Chicago, 1896, p. 195. 
VOL, LXXVII.—21. 
