MOLLUSCA. BRANCHIFERA. Bulla. 
Lamellaria mem. Mmt. Linn. Trans, xi. 184. t. xii. f. 3; the shell fig. 4» 
— English coast. 
Length and breadtlr about two inches ; of a brownish colour, paler above, 
and spotted with bluish-grey beneath ; tentacula subcylindric, with two eyes 
at the base ; a cylindrical snout ; shell ovate, very thin,^flat, with a minute 
lateral whorl ; silvery, tinged with pink. 
Gen. XLVI. BULLA. — Body in front with a fleshy expan- 
sion OF tentacular disc ; behind with a membranaceous ap- 
pendage or lid ; shell convoluted ; aperture the whole length 
of the shell. 
* Shells with a cuticle, external. 
170. ^.lignaria. — Shell ovate, spirally striated; mouth wide j 
anteally, rendering the pillar visible to the end. 
Concha veneris major leviter et dense striata, List. Conch, t. Ixxiv. f. 71.. 
— B. lig. Linn. Syst. i. 1184. Penn. Brit. Zool. iv. 116 B. scabra. 
Mull. ZooL Dan. t. ?1 — B. lig. Mont. Test. Brit. 205. — Not uncom- 
mon. 
I.ength upwards of 2 inches ; width l^th of an inch ; epidermis brown; aper- 
ture conti’acted reti’ally by the body-whorl ; the apex depressed ; pillar-lip 
rounded ; outer lip nearly straight ; gullet large, folded ; stomach fortified by 
three testaceous plates. 
171. B. ahera. — Shell ovate, smooth ; aperture wide, and ren- 
dering the pillar visible. 
Akera bullata. Mull. Zool. Dan. t. Ixxi. f. 2, 9.—B. resiliens, Lon. Brit.- 
Shells, t. Ixxix — B. akera, Mont. Test. Brit. 219.— On the shores of 
Banff and Devon. 
Length about fths of an inch ; breadth half an inch ; translucent, elastic, 
glossy, with a greenish tinge. Aperture wide anteally ; retrally it is very 
close to the body -whorl, but does not adhere until it has taken almost one vo- 
lution ; apex concave, exhibiting two or three volutions. The Bev. Charles 
Cordiner observed this shell in the Murray Frith, and transmitted specimens 
to the Duchess of Portland. — On some parts of the English coast it is not un- 
common. 
172. B. h^datis.—Shell subglobular, minutely striated spiral- 
ly ; aperture wide anteally ; the pillar-lip rounded, but the pil- 
lar not visible to the end. 
Linn. Syst. i. 1183. — B. ampulla, Penn. Brit. .Zool. iv. 116. — B. hyd. 
Z)o», Brit. Shells, t. Ixxxviii — On the English coast. 
Length 1 inch ; breadth fths ; translucent, with a brownish epidermis ; 
aperture interrupted by the rounded body-whorl ; apex concave, but not ex- 
hibiting volutions. Animal purplish-brown ; and, when expanded, double 
the length of the shell ; two eyes on the tentacular disc, sunk in small white 
depressions — Mont. Linn. Trans, ix. 106. t, vi. f. 1. 
173. B. Cranchii. — Shell subcylindrical, strongly striated spi- 
rally ; aperture narrow, rendering the continuation of the pillar 
invisible ; pillar-lip straight. 
Mf Prideaux, Plymouth Sound. 
