210 
the row of teeth swelling into the cavity of the shell be- 
neath the lunette, give the inside a beaked appearance : 
the hinge pit is minute. 
A small, though not unworthy present, from Miss 
Salisbury. I suppose it to be rare at Barton, as I have 
only seen a single valve. Figure 9 is the sketch of a 
cast from among a cluster that was found at Highgate: 
they appear to belong to a more gibbose, and perhaps 
curved species, but are not sufficient to decide from: the 
shell remains in part upon some of them in a very soft 
and friable state. 
N. minima may possibly be young of Arca minuta of 
Brocchi, Vol. II. p. 482; but it is only striated, not 
suleated ; and it differs from his A. nitida, in being ra- 
ther gibbose than depressed, and not truncated. 
