MOLLUSCA OF INDIA. To 
depresso, peripheria rotundata, basi lato ; apertura obliqua, lunato- 
subcirculari ; peristomate simplice, subinflewo, marginibus conniventi- 
bus, supero antrorsum subdilatato, columellart recedente, perarcuato. 
“Diam. 12, altit. vix 6 mill. 
“In the Botanic Garden of Calcutta; collected by Mr. Benson.” 
AUSTENIA BENSONI, Var. SYLHETENSIS. (Plate XX XVIII. fig. 3.) 
Locality. In a wood on bank of the Soorma river, about halfway 
between Atgaon and Chatak, Sylhet District. 
Shell depressedly ovate, thin, horny, shining, smooth surface ; 
colour dull olive-green ; spire flattened, rounded; suture shallow ; 
whorls 3, gradually increasing, the last tumid; aperture oblique, 
broadly ovate; peristome arcuate in front above; columellar margin 
oblique. 
Largest specimen :— 
Size: major diam. 10-3, minor diam. 8:5, alt. axis 4 mm. 
x3 0-41, 93 0345.) inn) OlGanch, 
This species differs from bensoni in the last whorl being more ex- 
panded in front, its thinner texture, and greener colour. The teeth 
of the radula are also modified in number, although of same type, 
as shown in Plate XX XVIII. figs. 2 and 3c; the central teeth being 
exactly similar in both forms, are not repeated. Their arrangement 
is 
G4 Oe AS ae 2 OF 
BO ens, 80 
(in 102 rows). 
The outermost (fig. 3c) are very small and show a tendency to be 
pectiniform, so characteristic of Durgella, and which in this case is 
evidently produced by the merging together at an early stage of de- 
velopment of two teeth into one. 
The left shell-lobe (fig. 3 6) is narrow, giving off a broad linguate 
process on the left margin; the left dorsal lobe is long and narrow, 
with a slight indentation opposite the above expansion. ‘These 
differences taken together, in spite of the similarity of the shells, 
incline me to consider A. sylhetensis a distinct species. 
Animal about an inch long; tentacles black; body light; extre- 
mity of foot mottled with black and green. The animal carries 
this extremity turned up (as shown in Plate XXXVIIL. fig. 3a, 
which are copied from drawings made by me from life). On the 
under surface is an opening, from which exudes the mucous matter 
as the creature crawls; it can be seen flowing down the underside 
of the foot in great quantity to the surface upon which it is moving. 
Shell in living animal dark, from the markings of the shell showing 
through it; the oral tentacles short and light coloured, situated very 
near the mouth. Another animal from the same locality was thus 
described in my field note-book :—* Light yellowish green ; tentacles 
darker, the lower light ; a very few dark markings near the gland at 
extremity of foot.” This, after all, is the same as the last species 
