210 
AMMONITES nodosus. 
TAB. XCII. — Fig. 5 . 
Spec. Char. Involute, depressed, keeled; volutions 
but little concealed ; radii straight for two-thirds 
of their length, then rising into a small knob, 
from which they extend towards the keel, curv- 
ing upwards, rather distant, with a gentle con- 
cave between them ; keel broad, obscure. 
The aperture is oblong, broadest towards the front, which 
is rounded; it is one-third the diameter long, and rather 
more than one-sixth wide? the keel, which is plain ex- 
ternally, is crenulated internally or on the cast. 
From Scarborough, by favor of Mr. Strangewayes ; it is 
in a dark brown clay. I think it undoubtedly belongs to 
the keeled division of Ammonites, as it agrees with them 
In general character, although the front is broad, and the 
keel obtuse o 
