188 Records of the Indian Museum. [VoL. VIE, 
V. DIGESTIVE SYSTEM (pl. xxv, figs. 6-13, and pl. xxvi, 
figs. 14-16). 
(i) The buccal bulb forms a tubular or elongated conical pro- 
boscis lying in a muscular sheath when retracted. The sheath 
opens on the ventral aspect of the head to form the mouth. The 
wall of the sheath is continuous behind with the wall of the buccal 
bulb just in front of the opening of the oesophagus into the latter. 
(ii) The buccal bulb is continuous behind with a thick-walled 
conical sac which forms the vadula sac. Collinge (3) describes the 
buccal bulb as divided into two portions lying respectively in front 
and behind the opening of the oesophagus. The radula sac is 
surrounded by a distinct muscular sheath. 
The vadula (pl. xxv, figs. II-13) is a wide ribbon-like struc- 
ture which does not seem to extend far forwards in the proboscis. 
The teeth are arranged in V-shaped rows with the apex of v directed 
backwards. There is no central. The lateral teeth are uniform 
in shape except the two median ones which are slightly different 
irom others. There is no marginal. There are never less than 19 
teeth on each side of the middle line. Each tooth is unicuspid 
and presents a shallow cup-like process in the middle. 
The teeth of the radula in A. strubelli (10) are similar to those 
of the present species except that there is no cup-like process in 
the former. 
(iii) The salivary glands could not be found in the specimens 
dissected. ‘They were described in several species of Atofos by 
Collinge (3, 4) and Simroth (12). Each gland was described to 
consist of a glandular mass and a long duct opening into the 
bucca bulb just behind the attachment of the muscular sheath 
on the ventral aspect. In A. savasint (4), the two glands unite 
to form a single mass, although the two ducts are separate. 
(iv) The oesophagus (pl. xxv, fig. 6) is a narrow tube arising 
from the dorsal surface of the buccal bulb behind the proboscis-sheath 
in the middle line or a little to its left. It then takes a U-shaped 
curve the bend of which is directed to the left. The tube then 
curves to the right, and down the side and ventral aspect of 
the anterior end of the radula sac to the mid ventral line, and 
then sharply turns forwards for some distance beneath the pro- 
boscis-sheath. It again turns backwards and passes beneath 
the short intercerebral connective to the undersurface of the 
digestive gland into the cavity of which it opens a little in front 
of the junction of the anterior one-third and posterior two-thirds 
of its length. 
In A. maximus (3), the oesophagus passes to the left and 
then takes a U-shaped curve to pass beneath the radula-sac, 
it then passes backwards and to the left beneath the inter- 
cerebral connective to the under surface of the digestive gland and 
opens into it at a point about one-fourth the length of the gland 
from the anterior end. In A. savasini, the oesophagus takes 
a similar sigmoid curve, but passes to the right at first and 
