24 DR. NELSON ANNANDALE ON ' 



Maximum diameter to 



height 1:1.07 1:1.11 1:1.11 1:1.1 1:1.11 



Maximum diameter to 



height of mouth 1:1.6 1:1.75 2.14 1:1.77 1:1.91 



Mouth to height 1 : 1.33 1 : 1.43 1 : 1.32 1 : 1.38 1 : 1.39 



Maximum diameter of mouth to 



maximum diameter 1:2 1 : 2.25 1 : 2.54 1 : 2.23 1 : 2.33 



The shell is slightly higher than broad and the mouth is 



from 1« to twice as high as broad. The total height is about If 



that of the mouth and the maximum diameter of the shell is from 



twice to 2* 7 times that of the mouth. 



The species was described from Pnom-Penh in Cambodia. I 

 have examined specimens (collected by Mr. Boden Kloss) from the 

 island of Koh Samesan off Cape Liant in the Gulf of Siam. 



JOURN. NAT. HIST. SOC. SIAM. 



