SCUDDER, ] TERTIARY LAKE BASIN OF FLORISSANT. 293 
Aix, in Provence, considered as eocene. But now, after a more careful 
revision, drawn from more extended sources, he writes that while, by 
the presence of many genera, “there is an evident relation of the Floris- 
sant flora with that of the Buropean miocene, yet by the affinities and 
even identity of some of the species with those of the flora of the gyp- 
sum of Aix, “which, according to Saporta, includes types related to those 
of the whole extent of the tertiaries from the upper cretaceous to the 
oligocene and above, I should rather refer this group to the lower mio- 
cene or oligocene.” 
Both Lesquereux and Cope agree in placing the Florissant beds at the 
same horizon as those of Elko, Nev., and also those directly above the 
Fish-cut beds at Green River, Wyoming. lLesquereux has identical 
species also from White River, Colorado, among specimens communi- 
cated by Mr. Denton. Cope calls the Florissant and Elko deposits the 
Amyzon beds, from the prevalence of that type of fish, and refers them 
to the ‘“‘later eocene or early miocene.” 
Mr. Clarence King places the Green River deposits in the middle 
eocene, but considers the Elko deposits of the same age. 
We may therefore provisionally conclude, from the evidence afforded 
by the plants and vertebrates, that the Florissant beds belong in or near 
the oligocene. 
' At present no geological conclusions can be drawn from what is known 
of the insects. So far as specific and generic determination has pro- 
ceeded, nothing identical has been found in the Green River and Floris- 
sant beds,* but some remarkable affinities have been noticed. To at- 
tempt, however, to draw any conclusion as to the age of either of these 
deposits, and especially of that of Florissant, before a closer examina- 
tion is made, would be folly. The entire series of fossil insects from the 
beds of Aix, Oeningen, and Radoboj requires a careful generic revision, 
the Coleoptera alone, perhaps, excepted, and until this is done it will be 
difficult to make much use of the information given us in the works of 
European authors. This should not be considered as reflecting upon the 
character of these works, for it must be remembered that they were nearly 
all completed thirty years ago and could not be expected to meet present 
demands. It is, indeed, not impossible that the richer American fields, 
the exploitation of which has only just begun, may yet be found the best 
basis for the study of the relationship of the tertiary insect faunas of 
Europe. 
*Some remains of egg cocoons of spiders are referred for convenience to the same 
species, but, of course, no weight whatever can be attached to obscure remains of this 
sort. 
