38 
CONVOLUTA.—6 GENERA. 
Shell without a canal, but having the base of the aperture channelled or effuse; the whorls large, 
compressed, convolute, the last nearly covering the whole of the others. 
Ovuta.—Shell turgid, attenuated at each end, the margins turned inwards: aperture lon- 
gitudinal, narrow, effuse at the extremities; without teeth on the left lip. 
(1) Right lip indented. 
Plate XIX. Fig. 16. O. oviformis. (Bulla ovum.—Linn.) 
(2) Right lip smooth, not indented. 
Plate XIX. Fig. 17. O. birostris. (Bulla birostris——Linn.) 
Cypra.—Shell oval, or ovate oblong, convex; the lips curved inwards: aperture longi- 
tudinal, narrow, toothed on both sides, the extremities effuse. Spire very small, 
hardly perceptible. 
Plate XIX. Fig. 18, 18 (a) C. talpa. (Idem.—Linn.) ; 
TrEREBELLUM.—Shell convolute, sub-cylindrical, pointed at the summit: aperture longi- 
tudinal, narrow at the upper part, notched at the base. Columella smooth, the 
lower part truncated. 
Plate XX. Fig. 1. T. subulatum. (Bulla terebellum.—Linn.) 
ANCILLARIA.—Shell oblong, sub-cylindrical, spire short, not channelled at the sutures: 
aperture longitudinal, scarcely notched at the base, effuse. A callous and oblique 
varix at the base of the columella. 
Plate XX. Fig. 2. A. cinnamomea. 
Outva.—Shell subcylindrical, convolute, smooth, spire short, sutures channelled: aper- 
ture longitudinal, notched at the base. Columella obliquely striated. 
Plate XX. Fig. 3. O. maura. (Voluta oliva, Variety.—Linn.) 
Conus.—Shell turbinated, or inversely conical, convolute: aperture longitudinal, narrow, 
not toothed; base effuse. 
(1) Shells coronated. 
Plate XX. Fig. 4. C. nocturnus. 
(2) Shells not coronated. 
Plate XX. Fig. 5. C. monile. (Idem,—Solander’s MSS.) 
