300 
PALAEONTOLOGY OF NEW-YORK. 
Position and locality. This species occurs in the soft shaly portions of the group, at 
Pulaski, Loraine, and other places. I have obtained casts of the same from the ferruginous 
sandstones in the higher part of the group. It occurs likewise at Cincinnati, and several 
other western localities. 
359. 3. ORTHONOTA CONTRACTA (n.sp.) 
Pl. LXXXII. Figs. 8 a, b. 
Subcylindrical, slightly arcuated ; beaks distinct, acute, with a prominent oblique carina 
extending towards the posterior basal margin, which is arcuated, and the shell much 
contracted below and posterior to the beaks ; dorsal margin broad, rounded, the valves 
strongly marked by oblique folds. 
The extremities of the shell are wanting in the two specimens which I have. It differs 
from the last, in having more acute and distinct beaks, with the cardinal margin broader. 
The base is arcuate, and distinctly contracted, or sinuate, a little behind the beaks. It is 
possible that this may prove identical with the last, since I have been unable to examine 
perfect specimens. 
Fig. 8 a. The left valve, showing the distinct carina and concentric striae of the surface. 
Fig. 8 b. Dorsal view of the same, showing the oblique wrinkles on the posterior cardinal margins of 
the shell. 
Position and locality. This species occurs in the soft marls at Cincinnati, Ohio. I have 
not seen it from other localities. 
360. 1. CLEIDOPHORUS PLANULATUS.* 
Pl. LXXXII. Figs. 9 a, b, c, d, e. 
JYuculites planulata. Conrad, Ann. Report, 1841, p. 48. 
— scitula. Conrad in MS. Emmons, Geol. Report, pag. 399, fig. 2. 
Subelliptical, with the anterior extremity narrowed, regularly rounded ; posterior side 
broader; beak scarcely elevated; a distinct impressed line extending from before the beak, 
* All the specimens of this species which I have examined, show no crenulations upon the cardinal margin, which 
is nearly direct and subalate posteriorly. There is no visible muscular impression as in Modiolopsis ; and the strong 
linear depressed line in the casts indicates the existence of a rib, or clavicle, as in Solecurtus. This character, which 
is very conspicuous in several species in the higher strata, pertains to shells having a similarity of form, which is 
nearly like the one figured. For shells of this character, I propose the following generic name: 
Genus CLEIDOPHORUS. 
[Greek, xXliSog, clavicle, and <p£po, to bear; in allusion to the clavicle in each valve, anterior to the beak.] 
The shells of this genus rnay be characterized as, equivalved, inequilateral; hinge without teeth or crenulations; 
surface (particularly in casts) marked by an oblique linear depression, extending from the anterior cardinal margin 
towards the base, indicating the place of the clavicle ; surface concentrically striated. 
