THE PALEONTOLOGIC RECORD 67 
THE PALEONTOLOGIC RECORD 
PALEONTOLOGIC EVIDENCES OF CLIMATE 
By T. W. STANTON 
U. S, GHOLOGICAL SURVEY 
e every one climate is an interesting theme. The climates of the 
past, especially when they can be shown to differ in character 
or distribution from those of the present, attract the attention of the 
general public, and they are of importance to the special student of 
geologic history whether his researches deal with the purely physical 
aspects of the subject or include some branch of paleontologic study. 
The evidence as to former climates comes from many sources. ‘The 
records of deposition and denudation in themselves sometimes give 
more or less definite indications concerning variations in temperature 
or moisture or both; the land floras when compared with those now 
living by their general characters and by the details of their structure, 
show more or less clearly the climatic conditions under which they 
lived; the land animals, especially the higher vertebrates, afford a good 
basis for inferring their habits and hence indirectly their environment, 
including climate; marine invertebrates give trustworthy evidence of 
differences in temperature of oceanic littoral waters at least in the later 
periods. It is obvious, however that the data furnished by any one of 
these lines of evidence will make only unconnected fragments of the 
history of past climates and that the evidence on the climate of any 
particular epoch, if derived from a single source, is seldom so complete 
or so convincing that corroborative testimony from other sources is not 
desirable. The subject is one in which general cooperation is essential. 
It should be stated at the outset that the most abundant and most 
definite evidence comes from paleobotany, and will be outlined in Mr. 
White’s paper. The discussion of the data derived from fossil verte- 
brates must also be left for some one who is qualified to present it, and 
the whole Paleozoic era may be passed over with the statement that so 
far as indications from the animal life are concerned the climate of 
the whole earth was mild and equable. The proof of local exceptions 
to this statement comes from other sources. 
All inferences from paleontologic evidence as to former climatic 
conditions rest in the final analysis on a comparison with the present 
distribution of animals and plants with reference to climate. Such 
comparisons may be general or specific, direct or indirect, and the con- 
