98 



CONCHOLOGY. 



P. labrossa. 

 P. fusus. 

 P. tridentata. 

 P. fasciolata. 

 P. zebra. 

 P. unicarinata. 

 P. maculosa. 

 P. clavulata. 

 P. ovularis. 

 P. Garmanica. 

 P. cinerea. 

 P. tridens. 



P. secale. 

 P. avena. 

 P. granum. 

 P. fragilis. 

 P. dolium. 

 P umbilicata. 

 P. muscorum. 

 P. angilicus. 

 P. rufescens. 

 P. edontulus. 

 P. odontostoma. 

 P. petiveriana. 



P. dentata. 



7. Genus Clausilia. PI. 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 situa- 

 tions both in Europe and America. Fifteen species. 



Clausilia torticollis. Clausilia denticulata. 



C. truncatula. C. collaris. 



C. retusa. C. papillaris. 



C. costulata. C. plicatula. 



C. corrugata. C, rugosa. 



C. inflata. C. gracilis. 



C. teres.* C. chrysalis. 



C. Meditenanea. 



8. Genus Bulimus. PI. 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 egg. 



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 



