PALZ ONTOLOGY. 111 
INOCERAMUS. Sowerby. al 
INOCERAMUS PROBLEMATICUS.—D. Orb. Palcont. 3, p. 510, Pl. 406. 
Inoceramus mytiloides.—Mantell. Geol. Sussex, p. 215, Pl. 28. 
Roemer, Kreide V. Texas, p. 60, Pl. VIT. 
Inoceramus pseudomytiloides.—Schiel. Beckwith’s Report. (P.R. R. R., Vol. II, p. 108, pl. 3, 
Jig. 8.) 
This species occurs abundantly in the limestone overlying the Cretaceous sandstone at the 
crossing of Red Fork of the Canadian, on the Santa Fé road. It is readily recognized by its 
elongated form and thin and finely undulate shell. 
It is widely distributed in Europe, and has been found in most parts of North America west 
of the Mississippi, where the Cretaceous strata are exposed. In Nebraska the place of the 
fossil is in the base of formation No. III and summit of No. II of Meek and Hayden’s Cretaceous 
section. 
This corresponds well with the position it holds on the banks of Red river, where I obtained 
it from the limestones which overlie the yellow sandstones of New Mexico; which last are the 
equivalents of Nos. I and II of the Cretaceous strata of Nebraska. 
The shell described by Dr. Schiel (loc. cit.) seems to be only one of the many phases presented 
by this Protean species. 
INOCERAMUS CRISPI (?)—Mantell. Foss. of South Downs, p. 133, Pl. XXVII, fig. 11. 
In the Lower Cretaceous strata at the Moqui ee: I found specimens of an Jnoceramus 
which I refer to this species. 
As our means of transportation were then quite exhausted I was compelled to content myself 
with few specimens of a kind, and it was only by abandoning a portion of our medicines that I 
could find room for even these 
Unfortunately the only large and perfect specimen of the Jnoceramus, to which I have referred, 
was crushed and nearly ruined on the way home; some small specimens were, however, 
preserved entire. 
A sketch which, as a matter of precaution, I took of the larger one when collected, shows the 
form of the shell to have been broad and rounded, the hinge-line comparatively long, the 
cardinal border joining the anterior margin almost at a right angle, and marked by a row of 
distinct teeth. The shell is thin, fibrous throughout—-as in most of the Lower Cretaceous 
species—strongly undulate; the concentric undulations widely separated and finely striated. 
In young specimens the fared is rather more elongate, the beak more acute, and the shell 
exceedingly thin and delicate.* 
PINNA. Linn. 
Pinna (?) LINGULA, (n. sp.) 
Shell elongate, arcuate, compressed, strap-shaped, narrow throughout; anal extremity slightly 
rounded; beak pointed, strong; external surface without longitudinal costa; internal surface 
without medial furrow; length, 6-7 inches; greatest breadth, 1.25 inch. 
I have referred this fossil to Pinna with much doubt, as some of the characters of that 
genus are wanting init. The general form, plain surface, and the absence of an internal fur- 
row assimilate it to Mytilus, with which it also accords in its gregarious habit, but the shell is 
apparently open at the anal extremity, and is composed of both lamellar and fibrous layers. — 
I have not been able to discover in my specimens, which are very sporti any indication 
of the existence of the peculiar hinge of Gervillia. 
®The smaller ones may not be the young of the larger; if not, they may be found to be identical with 7. fragilis, Hall 
and Meek. 
