27:3 
NAUTILOIDEA. 
are rather numerous, gently waved : the aperture is obtusely sagit- 
tate, with the posterior angles truncated ; umbilicus small, perha]is 
closed.” {J. Soiverhy.) 
A more exact description of the species may be given as 
follows: — Shell inflated, somewhat flattened upon the sides, rather 
narrowly rounded upon the periphery ; whorls deeply embracing. 
Umbilicus small. Septa moderately distant from each other, being 
IJ- inches apart upon the periphery in the type specimen, where 
the height of the whorl, measured from the umbilicus, is about 
inches. The sutures are bent backwards in a broad sinus on the 
Tig. (30. 
Xautilus eJegans. — a, lateral view of a cast, showing the sutures and ribbing ■ 
the umbilicus is partly filled with the matrix ; h, front view, showiug the 
position of the siphuncle. Drawn from 8owerby’s type specimen (No. oOTl) 
contained in the British Museum. A little more than one third natural 
size. 
sides of the shell, and are nearly straight on the periphery. 8iphuncle 
about its own diameter below the centre. Ornaments of the 
test (type specimen) consisting of regular, transverse, prominent 
ribs (flattened in casts), separated by interspaces about half the 
* width of the ribs, occasionally bifurcating, about sevcji of the ribs 
are contained in the space of an inch ; they are curved sigmoidally 
on the sides of the shell, and form a deep sinus upon the periphery. 
Bemarl's. The identity of this species has hitherto been completely 
mistaken, owing to the uncertainty existing as to the true character 
of Sowerby’s fossil, the type of which had not been recognized. 
