44 CLASS GASTEROPODA. 
jects from under the right tentaculum; the seminal fluid is 
conducted from the penis to the vulva by a groove which 
extends from one to the other. An enormous membranous 
crop leads to a muscular gizzard, armed internally with carti- 
laginous and pyramidal corpuscles; which is followed by a 
third stomach, sown with sharp hooks, and by a fourth, in the 
form ofa ccecum. The intestine is voluminous; and the ani- 
mal feeds on fucus. A limpid humour, secreted by a particu- 
lar gland, and which in certain species is said to be extremely 
acrid, is exuded through an orifice near the vulva; and from 
the edges of the mantle oozes an abundant liquid, of a deep 
purple colour, with which, when in danger, the animal tinges 
the water to a considerable extent. The eggs are deposited 
in long glairy strings, interlaced, and fine as packthread. 
In the seas of Europe we have Apl. fasciata, Poiret, Rang., 
Apl. pl. vi. vii.: black, bordered with lateral red crests. One 
of the large species. 
Apl. punctata, Cuv. Ann. du Mus. tome ii. p. 287, pl. 1. f. 
2—4; Rang. Apl. pl. xviii. f. 2: lilac, sprinkled with greenish 
_ points. 
Apl. depilatus, L., Bohatch. Anim. Mar. pl. i. and ii.; 
- Rang. pl. xvi.: blackish, with large greyish, clouded spots. 
Several other species are found in distant seas (Apl. brast- 
liana, &c.). Itis well, however, to observe, that most of the 
aplysie, having been drawn from specimens preserved in 
spirits, the truth of the specific characters of some of them 
may be doubted. 
DOLABELLA, Lam. 
The dolabellz only differ from the aplysiz in the position 
of the branchiz, and their surrounding envelope; they are 
at the posterior extremity of the body, which resembles a 
truncated cone. Their lateral crest presses closely on their 
branchial apparatus, merely leaving a narrow furrow. Their 
