2l6 GUPPY : MOLLUSCA OF TRINIDAD. 



bears a resemblance to the Stenopus cnientatus of Guilding. 

 From Guppya livida it differs widely in shape and structure. 

 In shape it is nearer to Zonites giiildingi, but it has a widely 

 open umbilicus and its colour and texture are very different. 

 The preseat shell is almost a miniature of Macrocyclis toy ana 

 Newc. (California). A caudal appendage has not been observed 

 in M. alicea^ but it nevertheless may exist. 



12. Helix coactiliata Fe'r. 

 Crosse, I.e. p. 40, No. 13. 

 Helix pnrkeri Tryon. 

 H. hridgesi Lea. 

 H. snturalis Pfeiffcr. 

 H. cordovana Pf. 



A planorbiform species recalling the European H. erice- 

 tortim. Its synon)my will partly indicate the wideness of its 

 distribution. 



Of the species of the genus Helix {sensu stridiore) found 

 in Trinidad this is the largest, the others all being minute. 

 This appears to be very rare and local, as I have only once 

 found it. Had it not been discovered under circumstances 

 which precluded the idea of its being introduced I should have 

 hesitated in retaining its name in the list of our local fauna. 



13. Helix bactricola Guppy. 



'Amer. Journ. Conch.,' 1870, p. 307, pi. xvii., f. 5. 

 Crosse, 'Journ. de Conch./ 1890, p. 39, No. 10. 



A small pyramidal deeply-umbiiicate fuscous-horny Helix, 

 with seven narrow slowly-increasing closely costellate whorls 

 carinate on the periphery. Height 2| mill., diameter 4 mill. 



I know of no very near ally to this shell. Its surface 

 ornamentation is somewhat like that of H. rotundata and other 

 members dfthe section Patula. Another shell having similar 

 ornamentation is Helix labyrinthica Say, but our H. bactricola 

 wants the reflector lip and the laminar tooth (or teeth) of that 

 shell, which, however, it approaches somewhat in general shape. 



J.C., vii., July iSq3, 



