ANATOMY OF ACHATINID^E. XV 



CALLISTOPLEPA (this vol., p. 125), has 'been examined by 

 Adolf d'Ailly, who unfortunately did not dissect it further 

 than to work out the dentition. The animal externally is 

 streaked and maculate with black or brown. Foot long, 

 slowly tapering towards the tail, with a triangular shell- 

 flattening above, bounded by serrate ridges. The radula has 

 unicuspid central and lateral teeth, the centrals about as wide 

 as the adjacent laterals. The marginal teeth acquire a small 

 ectocone, and the large cusp (mesocone + entocone) becomes 

 bifid (p. ix, fig. 2, C. barrianum. The teeth of C. shuttle- 

 worthi are similar). The anatomy is otherwise unknown. 

 This genus differs from all other Achatinince by the wide 

 middle teeth of the radula. 



Key to genera of Achatinina. 



I. Embryonic whorls except the first sculptured, forming a 

 large, semiglo'bose protoconch. 



a. Embryonic whorls densely striated spirally; lip of 

 the rather rudely sculptured shell expanded or re- 

 flexed. Pseudachatina, vol. xvi, p. 205. 

 aa. Embryonic whorls granose-decussate except the 

 smoothish first one. 



b. Protoconch bulbous or hemispherical; shell 

 ovate; viviparous South African forms. 



c. Columella abruptly truncate, Achatinoid. 



Cochlitoma, p. 76. 

 cc. Columella not truncate, blackish. 



Metachatina, vol. xvi, p. 307. 



bb. Protoconch very large; shell ovate, of only 5-7 

 whorls; columella Achatinoid. West Africa. 



Archachatina, p. 104. 



bbb. Shell cylindric or pillar-shaped, with Achati- 

 noid coloration and columella. 



Columna, p. 120. 



II. Embryonic whorls smoothish, without spiral sculpture or 

 granulation. 



a. Peristome well expanded or reflexed. 



Atopocochlis, xvi, p. 218. 



