244 PALEONTOLOGY OF NEW JERSEY. 
strongly modifies the form of the aperture and gives it a strongly reniform 
character; septa distant and very deeply concave, the sutures very nearly 
at right angles to the axis on the main portion of the volution, but form- 
ing a very slight backward sinus on the middle of the back, and also 
slightly bent backward within the umbilical depression as seen on the casts; 
siphon subcentral, a little nearer to the ventral than to the dorsal margin. 
Surface of the shell marked by fine transverse lines of growth which are 
arched strongly backward in crossing the middle of the shell, and forward 
on the sides. 
I have seen but few specimens of the casts of this species, and none 
showing remains of the substance except Dr. Morton’s type specimens, so 
the species does not appear to be common in New Jersey, although exten- 
sively identified from other parts of the country, usually, however, without 
direct comparison with New Jersey specimens. I have seen but few casts 
from other parts of the country which I should feel warranted in consider- 
ing as undoubtedly identical with the New Jersey shells; even those from 
the Black Hills, which are perhaps the nearest like it of any I have 
studied, differ very materially in general form. Dr. Morton’s type speci- 
men, which consists only of the outer chamber and forms but little more 
than half of a volution, shows the umbilical auriculations, and retains the 
shell in part, shows it to have had a solid axis and very broad aperture, in 
which it differs from any other which I have seen. The figures of this 
specimen given I think will present a somewhat different idea of the species 
from that which appears to have been usually entertained. 
Formation and locality: In the Lower Green Marls, at Burlington and 
Mullica Hill, and in Monmouth County, New Jersey, the latter being the 
type specimen of Dr. Morton, now in the cabinet of the Phila. Acad. Nat. 
Sci. 
NavutTiLus Bryanl. 
Plate XXXVIII, Figs. 5, 6. 
Nautilus Bryant Gabb: Proc. Acad. Nat. Sci., Phila., 1876, p. 277. 
Shell large and strong, somewhat compressed on the sides; giving a 
section to the volution, from the margin of the umbilicus to the dorsum, 
greater than the width from side to side. Umbilicus small, but open 
