MIOCENE MOLLUSCA AND CRUSTACEA. 99 
numerous revolving ribs which exhibit a slight tendency to alternate in 
size.” (Gabb.) 
The specimen which I have figured on the plate is the type from which 
Mr. Gabb drew his description. As he gives only a back view of the speci- 
men it is difficult to tell whether it is in the same condition now as when he 
used it. There is nothing of the outer lip showing at the present time, and 
the columella is also very imperfect; the columellar fold shows imperfectly 
and is quite oblique. The spiral or “revolving ribs” are very fine, and 
would be as well designated as impressed strize as ribs; they are very variable 
in size, and on the lower side of the whorl are flattened on the surface with 
a faint secondary line, giving the tendency to alternation mentioned. The 
substance of the shell is quite thick and the shell generally of a heavy char- 
acter. The transverse strize in crossing the spiral lines check them and give 
a rugose surface when seen under a glass. The species seems to have been 
somewhat uncommon. Mr. F. B. Meek in his Check List cites this species 
as from Texas. Under Mr. Gabb’s description he gives the locality as “with 
the above,” which is Cantharus Cumberlandiana, stated to be from Shiloh, 
N. J. So far as I can ascertain the species has not been recognized trom 
any other locality than New Jersey. 
Formation and locality: In the Miocene marls near Shiloh, N. J. From 
the collection at the Academy of Natural Sciences at Philadelphia. 
Genus LYROSOMA Conrad, 1862. 
Proc. Acad. Nat. Sci. Phila., 1862, p. 286. 
“Subpyriform ; ribbed, beak narrow and produced, slightly recurved; 
one long, very oblique plait at the angle of the columella. Fasciolaria 
(Fusus) sulcosa Conrad, Fossils Medial Tertiary.” 
The above is Mr. Conrad’s description and citation of type of this 
genus. The species for which the genus was proposed is a pyriform shell 
of small size, with a somewhat rounded spire and cancellated body, the 
strong spiral lines being crossed by vertical lines of growth, which divide 
the surface into quadrangular spaces, so as to present this checkered appear- 
ance. The only point that I can see which would warrant a separation 
from many of the forms of Fasciolaria, is the existence of a single fold on 
