20 
PRODUCTUS person at us. 
TAB. CCCXXI. 
Spec. Char. Hemispherical, irregularly stri- 
ated, beneath very concave ; within the 
larger valve are three deep cavities, one 
connected with the beak, and two remote. 
From the impressions of the cavities, which become 
protuberances, the cast of the larger valve has the ap- 
pearance of a bird’s head ; the remote ones are not very 
prominent, but are large ; that about the beak is divided 
into three lobes, of which the lateral ones are striated, 
and the central one is connected with the remote protu- 
berances by a ridge. The surface was probably covered 
with small spines, but this is not well ascertained. 
Such is the resemblance of this shell to a face, that 
the name person at us was thought apposite ; when less 
completely deprived of the shell than the specimen 
figured, there remain numerous small elevations which 
are probably the bases of spines, these have been taken 
for the roots of feathers, and so strong a resemblance was 
then found to an owl’s head, that the owner of a large 
specimen, which he brought to shew me, would hardly be 
persuaded that it could be any thing else. This speci- 
men was found in Derbyshire : the figure is taken from 
one picked up near Kendal. 
