Avaust 13, 1897. ] 
Vertebrate. The subjects of the former are 
generally to be found in an approximately 
complete condition so far as the exterior is 
concerned, and early attracted the attention 
of investigators, often little familiar with 
recent zoology, and received names. The 
subjects of the latter—especially the higher 
types, aS mammals, birds and reptiles—are 
rarely found, except in a fragmentary con- 
dition. Special knowledge of osteology, 
even to its minutest details, is requisite to 
successfully deal with such remains. Con- 
sequently the fossil vertebrates of the United 
States were neglected and left to the few 
who had cultivated the requisite knowledge 
to deal with them. 
Another reason existed for the tardy at- 
tention to Vertebrate paleontology, which 
continued till nearly the last quarter of our 
present century in the United States. No 
deposits containing many fossil vertebrate 
remains had become known in the Hast. 
Zoologists interested in the past and in the 
genealogy of existing forms lamented the 
poverty of the United States, which con- 
trasted with the richness of some parts 
of Europe. It was even thought that there 
was no hope of finding here such trophies 
of the past as the beds of the Paris Basin or 
those of Grecian Pikermi had yielded to 
European paleontologists. Butall this was 
to be changed. Rumor had long before 
hinted that numerous skeletal remains could 
be found in certain parts of the wild West, 
but the information was very vague. 
Enough was known, however, to induce 
Professor Marsh to visit certain deposits he 
had heard of. In 1870 he explored an 
Eocene lake-basin in Wyoming, drained by 
the Green river, the main tributary of the 
Colorado, and therein found numerous bones 
belonging to almost all parts of the skele- 
ton, of some remarkable gigantic mammals 
which he called Dinocerata. The results of 
this exploration interested Cope in the 
highest degree, He visited the same region 
SCIENCE. 
237 
in 1872, and thenceforth his attention to the 
Vertebrate paleontology of the Western 
States and Territories was never interrupted. 
An intense rivalry arose between Professor 
Marsh and himself which in time, it must 
be confessed, became very bitter. Never- 
theless, as in most quarrels respecting facts, 
investigations were provoked by mutual re- 
criminations which resulted in a more 
speedy accumulation of data and a more 
critical examination of those data than 
would have been likely under less perturbed 
conditions. Most of those data relate to 
morphological and anatomical considera- 
tions, and therefore belong rather to mam- 
malogy and herpetology than to geology. 
The relations of the ancient forms to each 
other in point of time; to those of other 
lands; and to those whose remains were em- 
bedded in other rocks, had necessarily to be 
investigated. The earliest conclusions of 
Cope were brought together and published 
in 1879 in a memoir on ‘The Relations of 
the Horizons of Extinct Vertebrata of 
Europe and North America.’* He at- 
tempted therein to synchronize, or, rather, 
homotaxially correlate the various ancient 
fauna of North America and ‘West Europe’ 
from the ‘Primordial’ to the ‘ Pliocene.’ 
Naturally the greater part of the memoir 
was devoted to the consideration of the Ter- 
tiary divisions; of these he admitted for 
the American form six primary divisions, 
and four of these were dichotomously sub- 
divided for the time. Of the primary-di- 
visions three were referred to the Hocene, 
one (White River) to the Oligocene, one 
(Loup Fork) to the Miocene, and one to 
the Pliocene. The exposition thus made 
represents views not very different from 
those now held, although, of course, modi- 
fications in details have since been nec- 
essary. 
The evolution of the various animal, and 
especially mammalian types, was also con- 
* Bull. U. 8. Survey Terr., V., 33-54. 
