242 PUSIOSTOMA. 



4. Buccinum. Outer lip thickened not reflected ; canal short ; 



including Cyllene and Phos. Fig. 416, 421, 422,425. 



5. Nassa. The same, with a notch or tooth at the extremity of 



the columella ; including Cyclops. Fig. 423, 424. 



6. Dolium. Swelled, grooved spirally ; outer lip not reflected. 



Fig. 420. 



7. Purpura. Aperture large ; columella!' lip flat; including 



Tritonidea. Fig. 414, 415. 



8. Monoceros. The same, with a tooth on the outer lip. 



Fig. 417. 



9. Concholepas. Patelliform ; aperture as large as the shell- 



Fig. 417. 



10. Ricinula. Columellar and outer lips granulated, denti- 



culated, outer lip digitated ; including Tribulus. Fig. 413. 



11. Trichotropis. Hairs on the epidermis, along the keels. 



Fig. 429. 



12. Terebra. Elongated, with a spiral groove near the suture 



of the whorls. Fig. 428. 



13. Bullta. Short; aperture wide; outer lip marginated. 



Fig. 427. 



14. E burn a. Like Buccinum, but the outer lip not thickened. 



Fig. 426. 



15. Harpa. With varices at regular intervals. Fig. 419. 

 PUSIA. Sw. A sub-genus of Tiara (Mitra.) (Sw. Malac. p. 320.) 

 PUSIODON. Sw. A genus of " Lucerninse," Sw. (Helix) thus 



described : " Shell flattened, smooth ; the body-whorl large, and 

 much dilated at the aperture ; spire small, flat, of three or four 

 contracted whorls ; aperture very oblique, sinuated, or obsoletely 

 toothed at the base of the outer lip, which is spreading and sub- 

 reflected ; inner lip obsolete ; umbilicus open. Zonaria Chemn. 

 132. f. 1188. auriculata Zool. 111. I. pi. 6." Sw. Malac. p. 330. 

 PUSIOSTOMA. Sw. A genus of the family " Columbellinse." 

 Sw. Thus described : " general form of Columbella, but the 

 outer lip is only toothed in the middle, where it is greatly 

 thickened ; inner lip convex between the granular teeth ; punc- 



