1897.] A Chapter in the History of Science. 853 
were imbedded in other rocks, had necessarily to be investi- 
gated. 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 Amer- 
ica.”* He attempted therein to synchronize, or rather, homo- 
taxially correlate the various ancient faunas 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 Tertiary divisions; of these he admitted 
for the American faunas six primary divisions, and four of these 
were dichotomously subdivided. Of the primary divisions 
three were referred to the Eocene, 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,{modifica- 
tions in details have since been necessary. 
The evolution of the various animal, and especially mam- 
malian types, were also continually the subject of Cope’s re- 
searches, and he attempted to trace the passage from those of 
the most ancient periods to those of later ones.” 
VIL 
Cope was not satisfied with the study of morphological de- 
tails or simple taxonomy. He aspired to know how animals 
came into existence; why they varied as they did, and what 
laws determined their being. His was an eminently philo- 
sophical mind, but at the same time with a decided tendency 
to metaphysical speculation. In one of his earliest papers he 
manifested this tendency and it persistod through life. It is 
with much hesitation that I venture to give an exposition of 
his most salient views, for I must confess I do not altogether 
like his philosophy and am able to subscribe to it only in part. 
* Bull. U. S. Survey Terr., V, 33-54. 
i a eah been reminded we aro Osborn of aa “ t disqovery of the Puerco— 
also the definition of the John Day and Deep river beds,” Prof. Osborn “adds, 
that “ practically the whole fauna of the Wasatch is also Cope’s.” I recognized 
these facts, but, as in herpetology and ichthyology, was obliged to limit my 
address and to refrain from going into details. 
