DESCRIPTION OF SHELLS. 175 
reason to think that the fibrous striated coat is more easily decomposed than the 
other lamin of the shell, and has therefore been generally destroyed ; such 
appears to have been the case often with the Bracklesham individuals ; however, 
some of the latter having the fibrous coat are almost free from striz, and others 
want them over more or less of the surface, which has induced me to consider 
the striated ones as only varieties of the others. 
MOLLUSCA GASTEROPODA. 
Emarginula obtusa. (Tab. IX. fig. 31.) 
Spec. Cuar.—Ovate, conical, depressed, radiated; principal radii 22-24, 
with one to three lesser radii between each, all granulated; marginal fissure 
shallow ; apex central, pointed, deflected. 
Length 3, height 1, width 13. 
The granulations upon the principal radii are coarse and transverse, being 
produced by the successive additions to the edge of the shell; the space filled 
up behind the fissure is crossed by strong lunate ridges and bordered by a thin 
plate, the reflected edge of the fissure. 
In the Cabinet of Mr. F. E. Edwards. 
Fissurella Edwardsii. (Tab. VII. fig. 9.) 
Spec. Cuar.—Ovate, with rather straight sides, depressed, finely radiated, 
and reticulated ; radii squamose ; apex pointed ; fissure oblong, its thickened 
internal margin truncated posteriorly ; margin crenulated. 
Length 4, height 14, width 3. 
Twenty or thirty of the radii are more prominent than the remainder, which 
are placed in sets of two or three between each of the larger ones ; they are all 
crossed by scales produced by elevated lines of growth. 
The figure is from a large specimen found by Mr. Edwards ; and Mr. Bower- 
bank possesses a small one which shows the inside; and Mr. Dixon has two 
specimens in his Cabinet. 
Infundibulum trochiforme. (Tab. XIV. fig. 27.) 
Varieties of this species, or species closely connected with it, are found in 
most parts of the tertiary formation ; but the characters are so irregular that it 
is almost impossible to define them. 
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