42 PALEONTOLOGY OF NEW-YORK. 
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70. 5. MURCHISONIA? VARICOSA (un. sp.). 
Pu. X. Figs..'7 a, 0. 
Turreted, or ovoidly conical ; volutions rapidly diminishing, angular, ventricose ; surface 
marked with longitudinal ribs or strong striz, which are crossed by transverse ridges, giving 
it a varicose appearance. 
The specimens which I have seen are obscure from the adhesion of stony matter, but 
the species seems well characterized and easily recognized, and it is therefore given in its 
imperfect condition. The lower volutions bear about two or three prominent ridges or 
angular elevations upon the upper side, while they are more regularly rounded below. 
Fig. 7 a. A specimen having the surface much worn and weathered : the markings are but partially 
visible. 
Fig. 7 b. Longitudinal section of a specimen of the same shell. 
Position and locality. This species occurs in the upper part of the Birdseye limestone, 
associated with Puytopsis and the preceding species of shells. It also occurs in the Black- 
river limestone, near its upper termination. Watertown, Jefferson county. 
71. 1. NATICA? 
( Species undetermined ) . 
Pu. X. Fig. 5. ; 
Volutions about four, rapidly enlarging from the apex, last one very ventricose ; surface 
smooth? ; suture apparently channelled ; spire but little elevated. 
This small shell is of rare occurrence in this rock, and I am by no means satisfied that it 
is distinct from a species of the Trenton limestone. It will be readily recognized from the 
figure. 
Position and locality. In the upper part of the Birdseye limestone, associated with 
Pleurotomaria, Phytopsis, and other fossils. Watertown, Jefferson county. 
72. 5. PLEUROTOMARIA? NUCLEOLATA (n. sp.). 
Pu. X. Fig. 6. 
Trochiform ;- spire short, rapidly tapering to an obtuse termination; volutions few, 
angular, flat above, the last one ventricose below ; suture canaliculate. 
The last volution composes nearly the entire shell, the upper ones being very small, and 
somewhat depressed. This is a small distinct species, which I have observed in no other 
position. : 
Fig. 6 a. Natural size of specimen. 
Fig. 6 b. Enlarged view of the same. 
Position and locality. In the upper part of the Birdseye limestone, with the last species. 
Watertown, Jefferson county. 
