40 : Say on Shells, &c. 
fatiscent. Amongst these I recognized a Crepidula, which 
differs from any | have seen, but is too imperfect to be de- 
scribed. A portion of an cbtusely rugose incrassated, Ser- 
pula. A Pecten which does not appear to have attained to 
its complete growth. A small laminated Cytherea, Lam. 
a Fissurella allied to F. greca, but immature. A Turri- 
tella, and fragments of a Balanus of considerable size, seve- 
ral specimens of a Nucula and of a Calyptraca. ‘The two 
latter may be described as follows. 
Nueula obliqua, valves obliquely subtriangular, obsoletely 
striate transversely, one or two of the strie more conspicu- 
ous, numerous, har dly perceptible longitudinal strie ; ante- 
rior and posterior sides forming an acute angle ; wmbo ob- 
tuse 5 apex acute 5 teeth angulated, prominent, cavity at the 
apex of the hinge profound, rather long ; basal margin den- 
ticulatocrenate. 
Greatest length one fifth of an inch.— 
Very much resembles Arca nucleus Lin. but is a smaller 
species, and proportionally narrower towards the apex, the 
hinge teeth are also more prominent and the cavity at the 
apex of the hinge is proportionally larger. 
Calyptrea costata, oval, convex, with numerous slightly 
elevated, equal equidistant coste, and crowded obtuse, con- 
centric lines, which are regularly undulated by the coste ; 
apex mamillated inclining to one side; ner valve pate- 
liform, dilated, attached by one side to the side of the shell, 
acutely angulated at the anterior junction, and rounded at 
the posterior junction, and rapidly tapering to an acute tip, 
which corresponds with the inner apex of the shell. 
Length nearly one inch— 
Seems to approach, in its characters to the genus Infundib- 
ulum of Montf. but from the fatiscent state of the specimens, 
this cannot be acurately determined. No definite spiral su- 
ture is perceptible. 
Genus Baculites, Lam. 
Shells straight, cylindrical, compressed, slightly conic, 
divided within into transverse septa, which are sinuous or 
ramose on their margins’and pierced with a siphunculus ; 
siphunculus at one extremity of the longest transverse di- 
ameter. 
