CONCHOLOGY. 105 
-P, exigua.* P. fallax 
P. armifera.* P. ovata.* 
P. pentadon.* 
7. Genus Clausilia. Pl. X. 
Animal. See Helix. 
Shell. Cylindrical, generally fusiform ; summit obtuse, the 
last whorl smaller than the preceding ; aperture irregular, rounded, 
oval; margin united, and externally reflected. Inhabits dry 
situations both in Europe and America. Fifteen species. 
Clausilia torticollis, Clausilla denticulata. 
C. truncatula. C. collaris.- 
C. retusa. C., papillaris. 
C. costulata. C. plicatula. 
C. corrugata. C. rugosa. 
C. inflata. C. gracilis. 
C. Mediterranea. C. chrysalis. 
C. teres.* 
8. Genus Bulimus. Pl. X. 
Animals of this genus in formation are precisely as the Helix ; 
they are, however, oviparous, producing eggs with the shell con- 
taining the animal perfectly matured ; they are frequently as large 
as a pigeon’s egs. 
Shell. Oval, sometimes turriculated, oblong; the summit of 
the spire obtuse, and the last whorl larger than all the others 
together; aperture oblong, oval, edge disunited ; in adults the lip 
much reflected ; columella smooth, with an inflection in the mid- 
dle, the base entire, not channeled. Inhabits mountainous situa- 
tions in Europe and America; some beautiful specimens have 
been found in the woods of Ohio. Sixty-three species. 
Bulimus ovatus. Bulimus multifasciatus. 
B. hemastomus. B. Bengalensis. 
B. gallina. B. Caribeorum. 
B. sultana, B. octonus. 
B. zigzag. B. terebraster. 
