96 CONCHOLOGY. 
B. fasciata. B. solida. 
B. striata. : B. cornea. 
B. Wyatii. B. lactea. 
B. solitaria.* B. hiemalis.* 
B. triticea.* B. Gouldii.* 
B. lineolata.* 
FAMILY VY. 
Aptystacea. ‘Two genera. 
1. Genus Dolabella. Pl. X. 
Animal. Body creeping, oblong, narrowed in front; and pos- 
teriorly widened; area round, sloping, and truncated obliquely ; 
margins folded over the back; four tubular tentacula, disposed 
in pairs; bronchial operculum inclosing a shell; orifice dorsal, 
near the branchie. 
Shell. Oblong, slightly arcuated, thick, callous, and somewhat 
spiral on both sides, singular in formation, and its characteristic 
unlike most other shells. Inhabits the Isle of France. Two 
species. 
Dolabella Rumphii. Dolabella fragilis. 
2. Genus Aplysia. Pl. X. 
Animal. Body creeping, oblong, convex above; bordered on 
each side by a broad mantle, which covers the back when the 
animal is in repose ; head and neck elevated, with four tentacula, 
the two upper ones ear-shaped, eyes situated near the mouth; 
dorsal shield simicircular, subcartilaginous, adhering on one side, 
and covering the branchial cavity. 
Shell. Nearly round, left margin somewhat reflected; outer 
lip acute; yellowish horn colored, with brown radiations, and two 
concentric bands. Inhabits the Indian seas. Thirty-seven 
species. 
Aplysia depilans. Aplysia hassetlii. 
“A. teremida. A. punctata. 
A. gigas. A. marmorata. 
