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AMMONITES striatulus. 
TAB. CCCCXXI. —fig. 1. 
Spec. Char. Discoid, carinated, radiated ; 
sides of the whorls convex; the inner 
whorls exposed; radii numerous, slender, 
undulated; surface covered with minute 
striae parallel to the radii ; aperture ellipti- 
cal. 
The whorls are about 6 ; their regularly convex sides, 
and numerous, small, twice curved ribs, and slightly 
relieved keel, give a symmetry to the general contour 
that is not easily recollected ; the diameter is nearly 
four times the length of the aperture ; the cast differs 
from the outer surface only in wanting the fine striae, or 
lines of growth, from which the name is taken. 
Found imbedded in a marly Limestone nodule, accom- 
panied with a portion of some fossil bone, on the coast 
in Robin Hoods Bay by Mr. Crawford of Scarborough. 
AMMONITES subradiatus. 
TAB. CCCCXXl.—jig. 2. 
Spec. Char. Lenticular, umbilicated, carina- 
ted, and radiated ; radii twice curved, ob- 
cure excepting near the margin, where they 
are bifid; umbilicus small; keel entire; 
aperture sagittate. 
T he edge of this lenticular Ammonite is rather obtuse, 
and the carina not much relieved ; the sides are nearly 
smooth, for the curved radii are very obscure excepting 
near the edge after they have become forked or divided, 
as some of them are, into three or even four short ribs ; 
the thickness is about one fifth of the diameter. 
Found several years ago on the road from Bath to 
Bristol ; it has been broken out of a mass of the Ironshot 
Oolite j no other specimen has reached our Cabinet. 
