NEW SPECIES OF CALYPTRAIDA. 199 
Diam. | poll., lat. 4, alt. ¢. 
Hab. ad Panamam. 
Found on stones in sandy mud, at a depth of from six to ten fathoms. 
8. CALYPTRHEA LIGNARIA. 
Tab. XXVII. Fig. 8. 
Cal. testd crassd, fuscd, deformi, striis corrugatd ; apice prominente, subadunco, acuto, 
posteriore. 
Diam. 1 ,*, poll., lat. ¢, alt. z. 
Hab. in America Centrali. (Real Llejos.) 
The majority of individuals of this species have their shells so deformed that they 
set description at defiance ; the comparatively well-formed shell occurs so rarely, that 
it may be almost considered as the exception to the rule. When in this last-mentioned 
state, the circumference of the shell is an irregular somewhat rounded oval, and it rises 
into a form somewhat resembling the back of Ancylus, with the apex very sharp and 
inclining downwards. The shell in this shape is generally less corrugated than it is in 
deformed individuals, though some of those are comparatively smooth; but, in both 
states, the shell is striated immediately under the apex, and is, for the most part, cor- 
rugated on the other side of it. 
Found under stones. 
Var. «. Enormiter conica, cyatho valdé profundo. 
Tab. XXVII. Fig. 8*. 
This variety is often one inch and six eighths in height, and its cup nearly one inch 
deep, while the diameter of the shell at the aperture does not exceed one inch. 
Found on shells in sandy mud, at the depth of four fathoms, at the island of Chiloe. 
9. CALYPTR#HA TENUIS. 
Tab. XXVII. Fig. 9. 
Cal. testd irregulari, tenui, subdiaphand, creberrimé striata, albidd, interdum fusco pallide 
strigatd. 
Diam. 1 poll., alt. =*,. 
Hab. ad Peruvie oras. (Samanco Bay.) 
Found on living shells in muddy sand, at a depth of nine fathoms. 
