Paleontological Discovery. 355 
— of our oa I have already laid before you on a 
In this rapid sketch of the history of Palsontology, I have 
vote it best to speak of the earlier periods more in detail, as 
are less generally known, and especially as they indicate 
ned growth of the science, and ats obstacles it had to surmount. 
With the present work in paleontology, moreover, you are e all 
more or less familiar, as the results are now part of the current 
literature. To assi ign every important discovery to its author, 
would have led me far beyond my present plan. I have only 
endeavored to indicate the growth of the science by citing the 
more prominent works that mark its progress, or illustrate the 
prevai rie SS and state of knowledge at the time they 
In mebaiaciog what has been accomplished, directly or indi- 
rectly, it is well to bear in mind that without paleontology 
there would have been no science of geology. The latter 
science — from the study of fossils, and not the reverse, 
hi nrg y supposed. Paleontology, therefore, is not a mere 
h of me sate but the foundation on which that science 
na ly rests. This fact is a sufficient excuse, if “ te — 
» for noting the'early opinions in regard .to the changes 0 
the earth’s a as diene ak hanges were first studied to explain 
the position of fossils. The investigation of the latter first led 
to theories of the earth’s formation, and thus to geology. When 
speculation replaced observation, fossils were discarded, and 
for a time the mineral characters of strata were thought to be 
the the key to their position and age. For some time after this, 
ts, as we have seen, aplenene for using fossils to deter- 
tine formations, but for the last half century their value for 
purpose has been full ized. 
The services which Poets has rendered to Botany 
and Zoology are less easy to estimate, but are very extensive. 
The classification of these seiences has been rendered much 
extinct types; while 
aphical a ae. of animals and 
