Dall's Tertiary Taitna of Tlorida. — Schnchcrt. 145 
'"When we remember that the successive Tertiary strata on our 
southeastern coastal plain are composed of nearly identical materials, 
one stratum being often built of the debris of those immediately preced- 
ing it; that their chemical and mineralogical constituents are necessarily 
practically the same ; that the soft nature of the rocks, even when con- 
solidated, lends itself to erosion and to obscuration by the subtropical 
luxuriant vegetation, — it would seem hardly necessary to reassert the 
truth so often lost sight of, that geological work which does not take 
careful account of the paleontological data in this region is practically 
futile. Nearly all the errors into which geologists have been led in this 
part of the country, practically all the inaccurate theorizing and inci- 
dental controversy, has arisen from ignorance of or too superficial ex- 
amination of the fossil contents of these rocks. The work already done 
is still insufficient for any final consensus of opinion. Those beds which 
have aflforded a well-preserved fauna are doubtless fairly well under- 
stood, that there are others like them not yet known is eminently 
probable, and that there are numerous others in which the removal of 
the fossils by solution has delayed recognition of their existence and 
relative importance is certain. The latter, affording only casts, or, in 
some fortunate cases, silicious pseudomorphs of the contained fossils. 
can only be intelligently studied when the intervening better-preserved 
faunas are thoroughly know-n. 
"Thus a rich field is open for the paleontologist, and the explorations 
and publications of the Wagner Institute have had exceptional impor- 
tance in calling attention to the opportunities it presents. It is earnestly 
to be hoped that the students needed to reap the harvest will soon be 
forthcoming. 
"The mapping out of the distribution of the different geological hori- 
zons from many isolated observations, * * * indicated that the peninsula 
ot Florida has experienced a tilting by which the eastern margin has 
been elevated between twenty and thirty feet, while the western coast 
has been depressed about the same amount. This tilting is supposed to 
have taken place since the Pliocene.* * * Mr. Wilcox finds that, off the 
streams falling into the Gulf of Mexico from the peninsula in the rela- 
tively shallow waters over the submerged plateau to the west, channels 
cut in the limestone may be traced for some distance. As these channels, 
too small to make any marked feature on the usual hydrographic chart, 
could not have been cut since the sea has covered the plateau, the infer- 
ence is obvious that they were cut Ijefore the tilting of the peninsula, 
when the limestone was above the level of the .sea. 
■'Dr. J. W. Spencer has propounded some very startling hypotheses, 
involving the elevation of some of the Antilles and Florida many thous- 
and feet and their submergence within a comparatively recent period of 
geological time. 
"By the researches of Professor R. T. Hill* and Mr. T. W. \'aughan 
much more light has been thrown on the subject. 
• Bull. Mus. Comp. Zool., vol. xvi, No. 15. pp. 2+3-288, 1895. 
