48 
Fam. 2. Craniade. 
The upper valve conic; the lower valve entire, flat. Attached to 
marine bodies by its outer surface. 
1. CRANIA. 
1. C. personata, t. 380. f. 1, 2, 3, t. 381. f. 5 (fig. 31). 
Fig. 31.—Crania personata. (Dorsal surface.) 
en mn 
Fam. 3. Discinide. 
The upper valve conical, patelloid; the lower orbicular, with a 
small slit in its disk, through which a short tendinous peduncle is 
emitted, by which it is attached. 
1. Discrna. 
1. D. Cumingi, t. 381. f. 9 (fig. 32). 
Fig. 32.—Diseina Cumingii. (Lower surface.) 
p, peduncle. 
Fam. 4. Lingulide. 
The valves free, nearly equal, elongate, and supported by a thick 
peduncle, which comes out between the beaks of the two valves. 
Periostraca hard, olive. Shell sometimes very thin, almost flexible. 
