14 GEOLOGICAL SURVEY OF THE TERRITORIES. 
appears never to have known F. forniculata. His original figures, in 
Emory’s Mex. Bound. Report, of G. navia, which he properly regarded as 
only a variety of G. pitchert, are unmistakable in their identity, and illus- 
trate a well-known torm which, although in a general way resembling, 
is distinctly different from EL. forniculata. Besides this, Mr. Conrad, in 
his accompanying description, refers, as already intimated, to Roemer’s 
figures in Kreid. von Texas, pl. ix, fig. 1 a, b, and ¢, as excellent repre- 
sentations of his G@. navia, which are also very different from H. fornicu- 
lata in their long vertically arched beaks. Mr. Gabb also refers to those 
figures of Reemer as illustrations of his G. mucronata ; and there is, there- 
fore, no room for doubt as to the mutual identity of the forms to which 
these two names were respectively applied by Mr. Conrad and Mr. Gabb. 
The latter author discriminated correctly between the true G. navia, as 
represented by Conrad’s and Roemer’s figures respectively, and H. for- 
niculata, and he possibly intended to give a new name to the latter form 
instead of the former; but he did not, and the latter has gone without 
a correctly-applied name until I published it as H#. forniculata in Proc. 
U.S. Nat. Museum, vol. ii, p. 293. 
Position and locality—Cretaceous strata, Bexar County, Texas, where 
it was collected by G. W. Marnoch, esq., together with many well-known 
Cretaceous species of that region. It is also found at numerous other 
Texan localities. 
Genus ANOMIA Linneeus. 
ANOMIA PROPATORIS (Sp. nov). 
Plate 12, figs 15 a and b. 
Shell rather small, irregularly and a little obliquely subovate or sub- 
circular in marginal outline; test pearlaceous and moderately thin, as is 
usual-in Anomia. Upper valve convex; beak small, depressed, not quite 
marginal; surface marked by somewhat coarse, irregular wrinkles of 
growth, by a few radiating wrinkles in the umbonal region, and by fine, 
close-set, raised, radiating strie, the latter appearing more distinctly 
on the forward part of the shell than elsewhere. Under valve unknown. 
Length of the most perfect example in the collection, 11 millimeters ; 
breadth, 10 millimeters; convexity, 5 millimeters. ‘i 
This shell resembles A.gryphorhynchus Meek, the typical examples of 
which are from the Laramie strata of the Bitter Creek series, Southern 
Wyoming, but it differs from that species in having aless prominent and 
rounded umbo; in possessing radiating and concentric wrinkles and 
radiating raised striee, while that species is an unusually smooth one. 
In the possession of the radiating raised striz it corresponds closely 
with A. micronema Meek, which is so commonly distributed throughout 
the Laramie Group. As this striation constitutes a more important 
characteristic than mere form, which is always variable in this genus, 
it strongly suggests an intimate genetic relation for our shell with A. 
micronemd. 
This species is a member of the estuary fauna which was discovered 
several years ago by Mr. Meek in the Cretaceous series of strata at 
Coalville, Utah, and which is more particularly mentioned on a subse- 
quent page, in remarks which follow the description of Cyrena carletont. 
Although all the species of that Cretaceous estuary fauna are different 
from any yet found in the Laramie Group, several of them are so closely 
related to certain Laramie forms as to strongly suggest the idea that 
