46 CLASS GASTEROPODA. 
very few whorls, and the animal is much too large to 
enter it. 
Bullea aperta, Lam.; Bulla aperta and Lobaria quadri- 
loba, Gm.; Phyline quadripartita, Ascan. Miill. Zool. Dan. 
1II. pl. ci.; Planc. Conch. Min. Not. pl. xi.; Cuv. Ann. du 
Mus. t. I. pl. xii. 6. The animal is whitish, and about an 
inch long; the fleshy shield formed by the vestiges of its ten- 
tacula, the lateral swellings of its foot, and the mantle occu- 
pied by the shell, seem to divide its upper surface into four 
lobes. Its thin, white, semi-diaphanous shell, is nearly all 
aperture, and its gizzard is armed with three very thick rhom- 
boidal pieces of bone. It is found in almost every sea, where 
it lives on oozy bottoms. 
The Sormet of Adanson is a species closely allied to Bul- 
lea; but I cannot establish a genus, or even a species, upon 
so imperfect a document. ' 
M. de Lamarck leaves the name of BULLA to those species 
whose shell, merely covered with a slight epidermis, is large 
enough to shelter the animal. It is somewhat more convoluted 
than in Bullea. 
The genus bulla of Linnzus not only comprised the akere, 
but also the auricule, agatine, physe, ovule, and terebelle, 
animals between which there is much difference. Bruguiéres 
commenced the work of reformation, by separating the aga- 
tine and the awricule, which he united with the lymnei to 
the genus bulimus. M. de Lamarck finished it by creating 
all the, genera we have just named. 
Bulla lignaria, L., Martini. I. xxi. 194—95; Cuv. Ann. 
du Mus. XVI. 1.; Pol. Test. Map. III. pl. xlvi. The oblong 
shell, with its concealed spire and ample aperture, very wide 
anteriorly, resembles a loosely rolled lamina, stretched in the 
direction of its whorls. ‘The stomach of the animal is armed 
with two large semi-oval osseous pieces, and with a small 
compressed one. Gioéni having observed this stomach sepa- 
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