40 CLASS III. GASTEROPODA. ORDER III. CERVICOBRANCHIATA. 
STOMATIA, Lamarck. 
Testa suborbicularis vel oblongo-auriformis, plus minusve depressa, im- 
perforata ; extus aut levis, aut striata, aut imbricata, aut carinata ; 
intus margaritacea; spira plerumque prominente, interdum incon- 
spicua ; apertura amplissima, szpils latitudine superante ; margini- 
bus integris, superné conjunctis. 
Although De Blainville has very widely separated the Stomatize and 
Stomatelle of Lamarck, we certainly cannot discover even a generic dif- 
ference between them ; we have therefore, in accordance with the opinion 
of Sowerby, united them. They were separated from the Haliotides by 
Lamarck on account of their shells not being perforated, and the Stoma- 
telle were afterwards distinguished from the Stomatiz, as having shells 
that are neither keeled nor ribbed. 
The shell of Stomatia may be described as being either suborbicular or 
of an oblong ear-shape, more or less depressed, and imperforate ; the out- 
side is either smooth, striated, imbricated, or carinated, the inside pearly ; 
the spire, though generally prominent, is sometimes almost inconspicuous ; 
the aperture is very large, and most frequently wider than it is long; the 
margins are entire and joined superiorly. 
Examples. 
Pl. CXLIX. Fig. 1. 
STOMATIA IMBRICATA, Sowerby, Genera of Shells, No. 19. Enc. Méth., 
pl. 450. f. 2. a, b. 
Stomatella imbricata, Lamarck. 
Pl. CXLIX. Fig. 2. 
STOMATIA SULCIFERA, Sowerby, Genera of Shells, No. 19. 
Stomatella sulcifera, Lamarck. 
