236 
for rumination do not exist in the hog. 
That any one mammalogist should make 
such a slip is not very surprising, but that 
a second equally learned should follow in 
his steps is a singular psychological curi- 
osity. 
I need scarcely add that the law of cor- 
relation applied by Cuvier to the structures 
of ruminants entirely fails in the case of 
many extinct mammals discovered since 
Cuvier’s days. Zadig would have been 
completely nonplussed if he could have seen 
the imprint of an Agriocheerid, a Unita- 
therid or a Menodontid. 
I have given this quotation for two rea- 
sons: first, to indicate how the increase of 
our knowledge has revolutionized old ¢on- 
ceptions; and second, to show how even the 
ablest of men may stumble. 
Cope has been much criticised for the 
mistakes and false generalizations he made. 
Unquestionably he did make many. But 
error seems to be inseparable from investi- 
gation, and if he made more than the other 
great masters he covered more ground and 
did more work. He was also, it must be 
admitted, more hasty than some others in 
that he availed himself of the more fre- 
quent means of publication he enjoyed. 
The great merit of Cope’s work on mam- 
mals is that he always considered the old 
and new—the extinct and recent—forms 
together. He refused to be bound by con- 
sistency or by precedent, either set by him- 
self or others. Fresh discoveries opened 
new vistas to him, and he modified his views 
from time to time and as often as he re- 
ceived new evidence. 
He introduced many new families in the 
system and sought to improve the system 
by the comparison of all the elements of the 
skeleton. He came to the conclusion that 
the affinities of the ungulate quadrupeds 
was best expressed by the manner of ar- 
ticulation of the bones of the carpus and 
tarsus; he associated those having the ‘ car- 
SCIENCE. 
[N. S. Von. VI. No. 137. 
pal and usually tarsal bones in linear series ” 
in a great order which he called Taxeopoda, 
and contrasted them with the Proboscidea 
and typical Ungulata, which he named anew 
Diplarthra. In the Taxeopoda he gathered 
many extinct families and associated with 
them forms of the existing fauna known as 
the Hyracoidea, Daubentonioidea, Quadru- 
mana and Anthropomorpha. I cannot al- 
together assent to this collocation inasmuch 
as I think the common characteristics of the 
three groups last mentioned—especially the 
structure of the brain and the development 
of the posterior cornua of the ventricles as 
well as calearine sulci—justify the old order 
Primates. Nevertheless an important char- 
acter was first appreciated in the composi- 
tion of the podial bones, and fresh insight 
was obtained into the relations of ancient 
types. 
I can only name a few more of Cope’s 
discoveries in this connection. One was the 
generalization of ‘trituberculy,’ or the origi- 
nal development of three tubercles to mo- 
lar teeth, and that subsequent modifications 
of the corresponding teeth were based on 
this original plan. Another was the re- 
markable Phenacodus of the Eocene, which 
was considered to be nearly in the line of 
descent for the ungulates as well as the 
series culminating in man and which led him 
to the conception of the taxeopodous group. 
The past history and genealogy of the 
Camels and their relations were likewise 
elucidated. In the present epoch only two 
nearly related types exist separated by half 
the globe—the true camels of central and 
northern Asia and the llamas of the Peru- 
vian Andes. Cope revealed numerous spe- 
cies from various Tertiary beds and showed 
that the type was originally richly devel- 
oped in America. 
VI. 
Paleontology from more than one point of 
view may be divided into Invertebrate and 
