GEOTROCHUS pileus. 

 Cap-shaped Land-trochus. 



Order Phytophages. Swains. Tribe 



Sub-Generic Character. 



Shell pyramidical, each volution, reckoning from the base, 

 gradually diminishing and forming a conic spire, basal 

 volution depressed, margin of the outer hp reflected and entire. 



Specific Character. 



Shell trochiform, smooth, generally banded ivith reddish and yellow- 

 ish bands : volutions convex. 



Trochus Pileus. Chemnetz. PL 122. f. 1046-7-8. 

 Helix pileus. Dillwyn. p. 933. No. 106. 

 Lister. Tab. 14. /. II. 



In Mus. Nost. 



Although this shell, in artificial arrangements, may be very 

 well placed among the sub -divisions oi Helix or Bulimits, 

 we feel persuaded that it is, naturally, the type of a Sub- 

 genus : we have no hesitation, therefore, in recording it as 

 such. Another species, sharply carinated, semi-transparent, 

 and of a milky whiteness, we discovered in Brazil : and we 

 are thus led to conclude that the habitat of Geotrochus 

 pileus, which no author has yet mentioned, may probably be 

 Tropical America. 



The figures of this species, given by Chemnitz and Born, 

 represent it as marked by several narrow bands of a rufous 

 brown colour: but the variety here delineated, has only one, 

 of a deep purple; it is almost the only specimen answering 

 to this description, which we have yet seen : both varieties 

 are very rare, and much prized by collectors. 



91. 



