202 S. H. Seudder—Rocky Mountain Triassic Insects. 
If this should be proved, Mr. Lake’s discovery will have an 
added interest, from the fact that almost nothing is known either 
of the plants or of the insects of this formation. Of the plants, 
it is only necessary to point out that in the paucity of data, the 
upper Paleozoic aspect of the few vegetable remains from Fair- 
lay can have but a negative value beside the positive proof of 
the alliance of the insects to Mesozoic forms. Of Triassic 
insects our knowledge is exceedingly meager ; a single neurop- 
terous larva from the Connecticut valley is all that the formation 
has hitherto yielded in this country. In Europe we know 0 
only four species, each, I believe, from a single specimen ; one 
of these is a cockroach, but it is entirely different from any of 
the Fairplay species, and indeed from any other known forms, 
so that we get no light from this quarter. 
It may be urged that as much the larger proportion of known 
Paleozoic cockroaches come from Europe, our own fauna being 
comparatively unworked, this discovery may only indicate for 
merica an earlier advance within Paleozoic times toward later 
types. Besides the important consideration that this would be 
in direct opposition to what we know of subsequent periods in 
e among fossil 
merica, there are only two facts known to m 
insects bearing on this point, one in favor of this hypothesis, the 
other against it. The first is the recent discovery in beds at 
Kansas City, Mo, said by the state geologists to have eight hun- 
dred feet of Carboniferous rocks ‘above them, of the wing of a 
heteropterous Hemipteron, which I have called Phthanocoris. — 
In Europe no instance is recorded of any insect belonging 10 
this great group of Hemiptera in Paleozoic rocks, the three oF 
four Hemiptera so far found belonging to the homopterous 
division. The other fact is brought forward in. my memoir 0D 
Paleozoic cockroaches, and is of far more importance, not only 
because it is of broader significance, but also because it is drawn 
from the same group as that under discussion. The Paleo- 
this continent. In Carboniferous times, therefore, as regards 
cockroaches, America was more old fashioned than Europe, and 
we should look for the introduction of new elements earlier 12 
Europe than in America; yet the better explored Carboniferous 
and Permian deposits of that continent have yielded no traces 
Pees ate tg aati 
Sr hae 
°° 
of anything akin to the Fairplay insects. The first appearance : 
of any such is in Mesozoic strata, and notably in the Lias. 
- §So far as I know this is the first attempt to determine the #g° 
of a deposit from its insect remains alone, and it is unfortunate . 
for its acceptance by naturalists that the plants give it, to say 
