PLAGUSIA DEPRESSA SAY. 469 



graphical range. The Museum contains also four speci- 

 mens of Plag. tuberculata Lam. from the Saughir Islands, 

 which differ from the specimens of depressa Say only by 

 the tubercles of the carapace being much more depressed. 

 The other characters , quoted by Mr. Miers , by which 

 these two forms may be distinguished, are of no imjjor- 

 tance , for allmost all our specimens of the West- African 

 depressa Say have the lobe above the bases of the second 

 and third ambulatory legs not dentated , and the terminal 

 segment of the postabdomen in the male of a Liberia 

 specimen is broadly semioval , that of a Sanghir individual 

 of tuberculata Lam. being narrower , with the sides more 

 distinctly convergent. 



Ley den, Febr. 1883. 



I>)"otes from the Leyden IVIuseuixi, Vol. V. 



