92 Contributions to Indian Malacology. [No. 2, 
In the Tsagain hills, west of the Irawady, opposite Ava, I obtained 
two forms, one bluntly angled at the periphery and approaching H. 
Oldhami, in which however the spire is lower and the umbilicus more 
open. The sculpture, form of the whorls and of the mouth, (which is 
rounded with connivent margins and expanded throughout,) and the 
angulation of the periphery, are precisely similar to the same characters 
in my specimens of H. tapeina : the umbilicus is slightly broader, and 
the spire lower, sometimes as flat as in Akoutongensis. The dimensions 
are 154 and 14 millem. in the two diameters; height 6. The other 
form is extremely sharply keeled and lenticular, with an angulate 
lunate mouth, and a narrower umbilicus than the last, or even than the 
Cherra tapeina, but it has the same simple sculpture, differing in this 
from the Shan hills form, which it otherwise resembles. It mea- 
sures 174 millem. by 16, and 9 in height. 
The next locality to the south in the Irawady valley at which I 
obtained forms of this type was at Thayet Myo. I have already re- 
ferred to the variety prevailing there, as well as at Prome and Akou- 
toung. Asa rule, the shells are small, thin, horny, and more or less 
hispid, very variable in the height of the spire, sharply keeled and 
with very fine, flexous striation. The major diameter is about 10 to 
12 millem. on an average. 
At Henzada, and in its neighbourhood, another form prevails. It 
is also met with at Akoutoung, but is rare, and it passes into the 
flatter form there prevailing. The Henzada shell has a much higher 
spire with very convex sides, and is, in fact, subcampanulate, the 
base, on the other hand, being flattened. It is sharply keeled, quite 
as sharply as the Akoutoung form, but it has the sculpture rather of 
H. tapeina than of rotatorza, and the epidermis, instead of being sub- 
hispid as in the latter shell, is merely granulate. A form, interme- 
diate both in height of spire and in sculpture between the Henzada 
and Akoutoung varieties, was found in the Arakan hills, between 
Prome and Tongoop. 
In the Bassein district, all the shells of this type are much the 
same. They have a sharp keel, moderate spire with convex sides, 
obtuse apex, and but little convexity beneath. They possess a granu- 
late epidermis and the sculpture of H. tapeina, 
The specimens with the highest spires, from Henzada, approximate 

