TROCHUS. TOP. Class VI. 



GENUS XXVI. TROCHUS. TOP. 



Animal, a Slug. 

 Shell conic, spiral. 

 Aperture sub-triangular, 



*& 



* Umbilicated, erect, columella perforated. 



1. magus. Lin. Syst. 1228. No. 585. Lin. Tr. viii. 151. 



tuberculated. Q m . £m. 3567. Mont. Test. Br. 283. 



Tr. with a perforated base; somewhat de- 

 pressed ; striated 5 with the ridges of the spires 

 rising into blunt distinct tubercles. Color 

 white, zig-zagged with red. 



When the upper coat is taken off, the next is 

 of a rich mother-of-pearl color. 



Anglesey. Tab. lxxxiii. Jig. 4. 



2. cinereus. Lin. Tr. viii. 152. Mont. Test. Br. 289- id. 



Sup. 119. 



* Tr. a tapering umbilicated shell, with distinct 

 plane volutions. 



