MOLLUSCA OF INDIA. 133 
tooth is tricuspid, the side cusps small and basal; in the median 
teeth there is only one very small external side cusp, up to the 22nd ; 
the laterals are then curved, uniformly pointed teeth, gradually 
becoming very small on the extreme margin. The jaw is slightly 
curved, with a small central projection. 
No genus, however, is constant over a large area; and thus we find 
in the species of Ariophanta east of the Bay of Bengal (A. retrorsa, 
Plate XXXLV. figs. 7,8,8a) that the radula and jaw are much modified 
—the central tooth more equally tricuspid, shorter, and all the 
laterals are bicuspid with even points, the jaw straight in front. 
I do not, however, possess another specimen in spirit to examine 
other parts of the anatomy. Professor Semper has, however, ex- 
amined several species from the Malayan region which he places in 
this genus (vide Reis. Phil. pl. 11. figs. 17-21), viz. :—rumpha, v. d. 
Busch, martini, Pfr., nemorensis, Mull., javanica, Lam., rarequttata, 
Mouss., striata, Gray, atrofusca, Alb, They all differ very much 
from the South-Indian form as regards the generative organs, es- 
pecially in the dart-sac with its large glandular extremity ; and as 
regards the odontophore, in those species (nemorensis and rareguttata) 
where the laterals are similar to the Burma form the centrals are 
unicuspid (/.¢. plate vil. figs. 6-8). Besides this, some, such as 
rareguttata, have shell-lobes, though generally small, which the 
Indian species do not possess. 
From these differences, all taken together, I consider the above 
species from the islands of the Malay archipelago to be a distinct 
group (vide J. A. 8. B. 1880, p. 153); but as I have not examined 
them or seen the animals myself, I refrain from giving them any 
subgeneric title. The sinistral form of the shell counts for very 
little; for instance, H. brookei, which some conchologists have 
on this single external character placed near this group, pos- 
sesses no mucous gland, and therefore cannot even be included 
among the Zonitide. It is very interesting though to note that it 
has a right and left shell-lobe. By Gray this species was placed in 
Nanina, and by Adams in Rhyssota, H. regalis, Bs.,=vittata, Adams 
and Reeve, from Borneo, is another species with a very doubtful 
generic position, placed in Ariophanta by Pfeiffer, in Nanina by 
Adams. 
The Indian species of Ariophanta are as follows :— 
ArtopHanra Layrprs, Miller. (Plate XX XIII. figs. 7, 7 a, white 
var.; animal, Plate XXXIV. fig. 1, from 576 of Stoliczka’s draw- 
ings, =trifasciata, Chemn.) 
Helix levipes, Mill. Hist. Verm. ii. p. 22. no. 222; Desh. in Fér. 
Hist. i. p. 177. no. 238; Kiister & Chemn. ed. nov. Heliv, ii. p. 107, 
£. 840 £522, 23) te 136, £82, 
Nanina (Ariophanta) levipes, Albers, Helic. p. 62. 
Helix levipes, Pfr. Mon. Helic. vol. i. p. 71, vol, ii. p. 75 ; Conch. 
Indica, p. vill (not figured). 
