332 



Records of the Indian Museum. 



[Vol. XVI, 



All well-grown males can be referred without the least hesita- 

 tion to one or other dimorphic form ; the " high " males reach a 

 larger size, the carapace being sometimes as much as 5'5 mm. in 

 length, whereas the ' low '' males rarely exceed 4'5 mm. In speci- 

 mens of medium size the characters of the sternum and chela are less 

 well developed, though as a rule perceptible, but in very small in- 

 dividuals, from 2'0 to 3'0 mm. in length, it is usually not possible 

 to detect them. The form of the copulatory appendage appears, 



Text-fig. io. — Dotilla intermedia, de Man. 



a. Chela of " high " male. d. Copulatory appendage of " high " 



b. Chela of " low " male. male. 



c. Copulatory appendage of "low" e. Abdominal .sternum of "high" 

 male. male. 



/. Abdominal sternum of *' low " male. 



however to be quite constant ; I have examined it in all the speci- 

 mens and have never once been in doubt. 



At Chandipur Dr. Gravely collected specimens on three occa- 

 sions, the numbers being as follows : — 



" Hig^h'' males. " Low" males. Females. 



June, 1915. '17 6 15 (I ovig.) 



May, 1916. 46 18 39(17 ovig.) 



May, 191 7. 41 20 33 (3ovig.) 



104 



44 



87 



