27 LAND AND FRESHWATER 
specimens from the Khasi Hills* shows that they vary very much in 
colour, from pale ochre to dark brown and even pale grey, while 
some are dappled, and others very much spotted on the mantle and 
sides (var. maculosus). I notice, too, that while some have the white 
raised rib near the periphery of the shell very well marked, in 
others it is absent, so that this is a most variable and unreliable 
character. It is apparently due, as is also the surface of the body, 
to the amount of atmospheric moisture at the time, and the size of 
the shell-lobes is greatly dependent on the same. 
Grrasta BuRTHU, G.-A. (Plate LXI. fig. 2, shell ; and Plate LXII. 
figs. 3, 3a.) 
Helicarion (Hoplites) burtii, Godwin-Austen, Journ. A. S. B. 
1876, p. 314, pl. vii. fig. 6. 
Girasia burtti, Godwin-Austen, P. Z. 8. 1880, p. 294. 
Original description :—* Shell dull white, very horny in texture, 
the apex scarcely developed, outline rounded above. Major diam. 
0°30. 
“Animal grey-brown in colour, the largest measuring as follows :— 
mantle to head 0’:40; mantle 0':80, mantle to extremity of foot 
0-50; or total length when moving 1'5.” 
Hab. The Borelli Tea Garden, near Tezpur, Assam; discovered 
by Mr. J. Burt, after whom I name it, and who found it abundant 
on the bark of trees during the rains (July). It is of the true 
typical form of Girasia, but in its very rudimentary, white, horny 
shell it is quite distinct from any of the other species I am ac- 
quainted with. I have since, through the kindness of Mr. D. McT. 
Lumsden, received a number from Paniputer Tea Garden, in the 
same district, north of the Brahmaputra; they vary somewhat in 
colour, and a few are mottled. Iam thus able to give some further 
details. The generative organs (Plate LXII. fig. 3) like type, the 
amatorial organ shorter and blunter. The jaw (Plate LXIL. fig. 3 a) 
curved in front, no central projection. The central teeth are narrow 
and long, with the small cusp low down on the outer side; the 7th 
and 8th are transitional in form, with the point of the outer cusp 
nearer to the main point; from the 9th outwards all are of the 
simple, evenly bicuspid form, becoming gradually smaller. (Plate 
LXII. fig. 3.) 
186002 tee Giley dina Gorge deve oe 
194.1 .194 
being many more than in G. hookerv. 
GrrastIA RADHA, G.-A. (Plate LX. figs. 6, 6 a, living animal.) 
Helicarion (Hoplites) radha, Godwin-Austen, Journ, A. 8. B, 1876, 
p. 314, pl. viii. fig. 4. 
Girasia radha, Godwin-Austen, P. Z. 8. 1880, p. 294. 
Original description :—* Shell similar to that of H. shillongensts. 
* Since sent me by Mr. M. Ogle. 
