Series in Kansas, Oklahoma and New Mexico. 225 
As has been previously shown by Roemer, this species greatly 
resembles Hxogyra matheroniana, an allied species, which in 
Europe also has a wide vertical range and extends as high as 
the Senonian. It was largely owing to its abundant occur- 
rence in Texas that Roemer made the cardinal mistake of con- 
sidering the Lower Cretaceous beds to be Upper. 
On the other hand, none of the many peculiarly charac- 
teristic Fredericksburg species of Texas occurs in the Kansas 
beds. 
Concerning the twenty-three species which Prof. Cragin 
describes and which have as yet been reported only from the 
Belvidere shales, the writer believes that many of them are 
due to the fact that they represent the naturally denser popu- 
lation of the more northern shallower littorals ; others will be 
found to occur in the rich unstudied littoral faunas of the 
Washita division in North Texas,* while some of them will 
be reduced to synonyms. ‘They all belong to that group of 
littoral genera with a wide range and of little value for minute 
correlation. 
The species called throughout this paper Gryphea fornicu- 
lata White is the same as the one from Comet Creek, Okla- 
homa, first figured by Prof. Marcou as Gryphea pitchers 
Morton,t and later called by him Gryphea Remeri.t The 
nomenclature of the Gryphzata oysters of the Comanche 
series will be thoroughly revised in a separate paper which 
the writer has in print. Prof. Marcou’s name G. Remere 
probably has precedence over G. forniculata White, but it 
may be shown neither of these will stand. 
This Gryphzea so abundant at Belvidere is likewise found in 
great numbers in the Kiamitia clays, not only about Denison 
and Fort Worth, but also along a persistent line of 300 miles 
from Goodland, Indian Territory, to south of the Brazos in 
Texas. Its hemera in Texas is exclusively confined to the 
Preston beds, and Prof. Marcou has always held that it is a 
Cretaceous form; it is the species upon which he established 
the existence of the alleged Neocomian in America. 
An interesting fact in the Black Hills and Blue Cut sections 
is that the large Grypheea which comes in near the top of the 
shales is identical with the form collected by Prof. Marcou 
and is the species called Gryphwa tueumcari by him (later 
ealled Gryphea dilatata var. tucumcearit).§ 
* Since penning these words Prof. Cragin himself has already verified this 
prophecy by publishing many species from the Denison beds which emphasize 
this assertion. See Fifth Annual Publication, Colorado College Studies, received 
April, 1895. 
+ Geology of North America, Plate IV, fig. 5, 5a, 6. 
t Proc. Boston Soc. Natural History, 1861, p. 98. 
§ Loc. cit., Pl. IV, fig. 1, la, 2. 
