1104 The American Naturalist. [November, 
but now generally referred to reptiles, have been found. Only a few 
plants are known from this region. This-series of rocks extends 
through New Jersey and Pennsylvania to Virginiaand North Carolina. 
An outcrop of rocks, presumably of this age, is now known on the 
Potomac, about twenty miles from Washington. From this point the 
series passes passes south in a narrow belt, ten or fifteen miles wide, as 
far as Charlottesville, and is thought to be connected with the Rich- 
mond coal field, also Triassic in age. This coal field has yielded many 
species of fossil plants. They were collected by Rogers, Lyell, Em- 
mons, and others, but no very systematic study has been given the 
field until recently. Rogers referred the beds to the Oolite of York- 
shire ; Emmons referred them to the Permian ; Fontaine, within a few 
years, placed them in the Rhætic, somewhere between the Triassic and 
Jurassic. The view of Cope, and the one toward which Prof. Ward in- 
clines, is that the Richmond beds, the North Carolina beds, and those 
of the Connecticut River, really are all of Triassic age, and equivalent 
to the Keuper group, the upper member of the Triassic in Europe. 
The total number of plants known from the horizon in North America 
is comprised in 51 genera and 119 species. These are distributed as 
follows : 
Genus, Species, 
Problematical organisms, . . . . . 5 9 
FREE 1 s s. ee 2 RE ie 16 36 
Rapnmetareie. V s rm 2 8 
bhyeonodace, ull. EY I I 
Era, none, 12 35 
Conie o o RoS : 8 19 
Monocotyledons, re es A M P E 2 a 
Do : 
[AME o te DUUM ep t 9 
The Triassic area is divided into five basins, viz., the Connecticut 
valley, New Jersey and Pennsylvania, Virginia, North Carolina, and 
the western area. The species are distributed as follows : 
Totalnumber. Peculiar to each. 
Connecticut River Valley, . . 23 13 
New Jersey and Pennsylvania, 18 5 
en ee 56 34 
North Carolina, . . 2... 52 25 
Westen ENMA E cia x H 
13 
About one-half the number found in the United States occur also in 
Europe, the largest number of identical species being in the Rheetic, 
-~ and the next largest in the Keuper. 
