103 
NUCULA deltoidea. 
TAB. DLIV.— /g. 1. 
Spec. Char. Triangular,, inflated ; posterior side 
obliquely truncated, flat, pointed ; anterior 
side short, rounded. 
Syn. Nucula deltoidea, Lamarck, Env. de Paris, 194. 
Hist. Nat. vi. 60. 
A pretty little shell, unlike any other species of Nu- 
cula : it is generally smooth, but is sometimes longitu- 
dinally striated, especially near the anterior margin. 
Very abundant in some parts of the Clay of the so called 
upper marine formation on the Isle of Wight. 
Specimens are sometimes found at Grignon half as 
wide as the larger figures** which are magnified. 
NUCULA inflata. 
TAB. DLIV.— fig. 2. 
Spec. Char. Nearly globular, smooth ; the pos- 
terior side produced, compressed, pointed. 
Large individuals of this shell are transversely oblong; 
the small ones heart-shaped or nearly globose ; the pro- 
duced side is small. 
Found in Septaria in the London Clay at Highgate, in 
1810. I have been favoured with casts in pyrites from 
Southend, by the Rev. F. W. Hope, who has made a 
very extensive collection at that place. 
