UTICA SLATE AND HUDSON-RIVER GROUP. 297 
353. 13. MODIOLOPSIS CURTA (1. sp.). 
Pu. LXXXI. Fig. 4; Pu. LXXXIL. Figs. 2 a-d. 
Compare Cypricardites curta. Conrap, Ann. Geol. Report, 1841, p. 53. 
Suborbicular, compressed, oblique; cardinal margin short; anterior extremity rounded, 
posterior obliquely truncated; base curving; beak distant from the anterior extremity 
nearly one third the length of the shell; surface marked by concentric undulations and 
finer strie. 
In specimens not compressed, there is an obtuse oblique carina, extending from the 
beak to the posterior margin above the base; but when the shell is compressed, this feature 
is obliterated. The concentric fine striz are usually obliterated when the matrix is arena- 
ceous, and they are only indistinctly preserved in specimens from the shale. This one is 
quite unlike either of the preceding forms, and deviates widely from typical forms of the 
genus. A single specimen preserves the mark of the anterior muscular impression. 
Pirate LXXXI. 
Fig. 4. A large individual of this species, from near Grimsby, Canada West. 
Puate LXXXII. 
Fig. 2 a. A specimen from Loraine, Jefferson county, New-York. 
Fig. 2 6, A small specimen in shale, from Rodman, Jefferson county. 
Fig. 2 c. Figure of a small specimen from Mineral Point, Wisconsin. 
Fig. 2 d. Cardinal view of the same. 
Position and locality. This species occurs at Loraine, in the higher shaly part of the 
group; in the lower part of the same in the town of Rodman; and in a similar position 
near Rome, Oneida county. It is found in the same group in Canada, and in a similar 
position at Mineral Point ( Wisconsin ), and several other western localities. 
354... 14. MODIOLOPSIS ( Species undetermined) . 
Pu. LXXXI. Figs. 5 a, 0. 
Subcylindrical, elongated, very gradually expanding from the anterior extremity ; beaks 
subacute, near the anterior extremity ; surface smooth or with fine concentric strie. 
The specimen is imperfect at both extremities, but sufficient is preserved to show that it 
is a distinct species. In the perfect shell the beaks extend nearly or quite as far as the line 
of the anterior margin. 
Fig. 5 a. Left valve of the fragment. 5 8. Dorsal view of the same. 
Position and locality. This species is known to me only in the soft shales of Cincinnati 
( Ohio). 
| PatzonTotocy. ] 38 
