1919.] N. ANNANDALE & B. PRASHAD: Gastropod Molluscs. 115 
might be expected in an adult shell, The measurements are as 
follows :—Height 7 mm., maximum diameter 3°5 mm., height of 
mouth 4°77 mm., maximum diameter of mouth 2°2 mm. 
The species is only known in what may be a subfossil state. 
It has been found on the banks of the lower Euphrates at two 
places, in Seistan, and in the Afghan desert to the south-east of 
that district. The Gaud-i-Zirreh is a great basin of strongly 
saline marshland into which the Helmand river at one time drained. 
See p. 4 and plate r of this volume. 
The adult shell is still more like that of L. truncatula than 
the young, but the same differences persist in a sufficiently strong 
degree for specific separation. The Mesopotamian specimens we 
have examined are all young. 
RT Ne <4 we 
