GASTROCOPTA, MASCARENE ISLANDS, ETC. 127 



inent bifid parietal fold; an acute basal tooth; an entering 

 bifurcate coluniellar fold. Length 2, width 1 mm. 



"Under low trees at base of Elandsberg Mountains (Far- 

 quhar) . A ventricose little species, with continuous peristome 

 and complicated arrangement of mouth-processes" (Melvill 

 & Ponsonby}. 



73. GASTROCOPTA DUPLICATA (Preston). PL 41, fig. 3. 



Shell small, sinistral, cylindrically ovate, rimate, brown; 

 whorls 5, the first four regularly increasing, the last ascend- 

 ing in front, having a somewhat weathered appearance; 

 suture well impressed ; umbilicus reduced to a narrow chink ; 

 columella descending in a curve, labrum continuous, white, 

 slightly reflexed, obtusely angled above on the outer side ; 

 aperture roundly ovate, armed with two short, erect, parietal 

 lamellas placed the one almost above the other, the lower of 

 which is very interiorly situate, a tubercular lamella 011 the 

 columella and a sub-basal lamella on the outer lip, above 

 which and well inside the shell occurs a small denticle. Alt. 

 3.25, diam. maj. 1.75 mm. ; aperture : alt. 1, diam. .5 mm. 

 (Preston}. 



British East Africa : between Rumruti and Mount Kenia. 



Fauxulus duplicatus PRESTON, Ann. Mag. N. H. (8), vii, 

 May, 1911, p. 470, pi. 11, f. 22. 



The figure, copied from Preston's, is very poor. The species 

 is certainly not a Fauxulus. It appears to be a sinistral 

 Gastrocopta. The name is prior to Bifidaria duplicata Sterki, 

 which may be called Gastrocopta procera sterkiana (p. 65). 



Species of the Mascarene and other Islands in the Indian 



Ocean (Bourbon, Mauritius, Rodriguez, Seychelles, 



Comoros, Nossi-be). 



These forms are illustrated on plate 23. They belong to 

 the typical subgenus Gastrocopta. They are so closely inter- 

 related that one is inclined to think them local races of a 

 single species, which may have been carried about on plants 

 within the period of human occupation. The resemblance to 

 the equally widespread Antillean species G. servili-s is very 



