213 
NAUTILUS sinuatus. 
TAB. CXCIV. 
Spec. Char. Thicks umbilicate, concentrically 
striated ; side depressed,, conical ; front con- 
vex ; aperture obtusely sagittate, truncated ; 
the septa have a large sinus on each side. 
The most remarkable character of this Nautilus is, the 
large marginal rounded sinus or lobe on each side the 
septum : the septum is also much elevated towards the 
front. The striae are nearly close together, moderately 
fine, and elevated : they gradually disappear towards the 
mouth. The inner whorls are wholly concealed, and 
few. The greatest diameter is equal to twice the thick- 
ness. 
For the use of the only specimen I have seen of this, 
I suppose rare as well as remarkable shell, I am indebted 
to the well known author, Mr. Parkinson. It was found 
somewhere near Yeovil, but Mr. Parkinson is not ac- 
quainted with the exact locality. It appears to belong 
to the inferior Oolite : its chambers are lined with car- 
bonate of lime stained with iron, and partly crystallized 
in acute rhombs. It is not broken so as to shew the 
situation of the siphunculus. 
