127 
GRYPELEA gigantea. 
TAB. CCCXC1. 
Spec. Char. Orbicular, rather smooth ; upper 
valve thin, concave ; lower valve convex 
with a small, sharp, incurved beak ; hinge 
small. 
A large, regularly formed shell ; the edges of the im- 
bricated laminae of the lesser valve, are but little eleva- 
ted; they are even, and placed at regular intervals. The 
small hinge pit distinguishes this species from G.dilata- 
ta, tab. 149. The anterior lobe, is separated from the 
rest of the shell, by a small sinus in the edge of each of 
the laminae: The length and breadth are nearly equal, 
the depth is about one fifth of the length. 
In the description of G. dilatata, tab. 149, this shell 
has been unfortunately confounded with that species, 
owing to the want of such specimens as possessed the 
specific distinctions ; it appears that the one before us, 
is confined to the inferior, or Iron shot Oolite, while 
variety a of the dilatata belongs to the Clunch Clay and 
others to the Kelloways Rock. 
GRYPELEA globosa. 
TAB. CCCXCIL 
Spec. Char. Subglobose, oblique, smooth, 
thin ; beak largely truncated ; upper valve 
immersed, concave. 
Syn. Ostrea vessicularis, Lam. Hist. Nat. 
VI. pt. 1. p. 218. Cuvier and Hrogniart, 
env . de Paris , ed. 1822, 383, tab. 3 .fig. o. 
Podopsis gryphseoides, Lam . Hist . Nat . VI. 
pt. 1, 1 95. 
T« large surface by which this shell is generally 
attached entirely destroys the curved form of the beak, 
usually met with ina Gryphite ; thefree portion risesfrom 
the substance to which it is attached in a very bold curve 
almost forming a cup with a concave, immersed lid, but 
