108 Records of the Indian Museum. [VoL. XVIII, 
Three specimens in spirit collected by Capt. Boulenger in ponds 
connected with the Khandag Creek in a palm-grove near Basra 
seem to belong to this species. The shells are, however, thicker and 
are sculptured with curious flattened opaque ribs on the body-whorl. 
The form is also narrower, perhaps because the specimens had not 
reached their full growth, and the basal whorl of the spire is smaller 
and not so distinctly separated from the body-whorl. Otherwise 
the spire has the characteristic features of Hutton’s species. A shell 
is I0o°5 mm. long, and its maximum diameter is 6 mm. 
The three shells are all more or less broken. With more 
abundant material racial differences might perhaps be found between 
shells from the eastern parts of the range of the species and those 
from Mesopotamia. 
The radula of a specimen has the approximate formula 18.8.1. 
8.18. The asymmetry of the cusps of the central tooth is very 
distinctly marked, as also is its tridentate character. ‘The inner cusp. 
of the lateral tooth though situated at a higher level than the outer 
is not much larger; all the cusps of the laterals, however, are 
pointed, differing in this respect from those of the Seistan specimens. 
The marginals have four to seven blunt cusps, all situated in the 
same straight line, and one or two small pointed cusps situated on 
the outer margins of the teeth near the base. 
The genitalia. Owing to paucity of material and to the speci- 
mens being very much contracted we are not able to add much 
to our previous account. The genitalia of a Mesopotamian speci- 
men resemble those of specimens from Seistan except that the 
uterine duct is much thicker at its commencement, the prostate 
is better developed and lies a little higher up on the male duct, 
which also is much thicker in its proximal part. ‘These differ- 
ences may be due at any rate in part to the state of sexual activity 
in which the molluscs were killed. 
Limnaea peregra race canalifera, Mousson. 
(BE XE, fies. 1,72.) 
1874. Limnaea canalifera, Mousson, Fourn. de Conchyl. XXI, p. 41. 
1918. Limnaea peregriformis, Annandale, Rec. Ind. Mus. XV, p. 165, 
Diese ares eal, 
This is much the largest form of Limnaea known to us from 
Mesopotamia, and the only one in which the shell grows more 
than 20 mm. long. The shell is also stouter and more coarsely 
sculptured than that of other species from the lower Euphrates. 
It has as a rule—though the fact is not mentioned in the original 
description—one more whorl, 7.e. five whorls instead of four. 
In dorsal view the shell is very asymmetrical bilaterally. The 
spire is acuminate, conical, vertical, exserted but short, but not 
so short as that of other shells of the same group from Meso- 
potamia, being at least (in adult shells) 1 as long as the body- 
whorl. Its whorls increase rapidly and evenly iu size and the 
spiral between them is oblique, linear and somewhat impressed. 
