250 Records of the Indian Museum. [Vol. Ill, 



merus of the chelipeds : the exopodite of the external maxillipeds 

 carries a strong plumose flagellum. — Type P. tridentata, A, M.-Edw. 



2. Subgenus Leschcnaultia, nov. The antero-lateral borders of 

 the cara])ace are )iot spinose : there is no subterminal spine on the 

 upper border of the merus of the chelipeds : the epigastric crests 

 of the carapace are in advance of and quite independent of the 

 post-orbital crests : the exopodite of the external maxillipeds carries 

 a strong plumose flagellum. — T^-pe L. hydrodromus (Herbst). 



3. vSubgenus Phricote'phusa, nov. As LeschenauUia , but the 

 flagellum of the exopodite of the external maxillipeds is either 

 absent, or vestigial, or filamentous, or is inconstant in one and the 

 same species ; and the antennal flagellum is minute or vestigial. — 

 Type P. callianira (de Man). 



4. Subgenus Barytelphnsa, nov. As Leschenaultia , but the 

 epigastric and post-orbital crests are either united to form a single 

 ridge, or else are in the same line and are imperfectly separated 

 only by a vague break : the cervical groove is usually very broad 

 and very deep. — Type B. jacquemontii ( = " Telphusa indica"). 



5. Subgenus Liotelphusa, nov. As Leschenaultia, but the 

 epigastric and post-orbital crests are low and quite inconspicuous, 

 and the lateral epibranchial tooth is small or obsolescent. — Type 

 L. Icevis (W.-M.). 



6. vSubgenus Glohitelphusa, nov. As Leschenaultia, but the 

 epigastric and post-orbital crests are still more inconspicuous than 

 in Liotelphusa, the lateral epibranchial spine is obsolete, and the 

 exopodite of the external maxillipeds is short and non-flagellate. — 

 Type G. bakeri, A. A, 



Certain new species of Potamon and Potamiscus have been 

 briefly noticed in papers Nos. i and 2, the following new species 

 of other subgenera may now be mentioned preliminary to the full 

 diagnoses that will appear in m}^ forthcoming report on the Indian 

 Potamonid?e. 



Genus Potamon. 



Subgenus Geotelphusa. 



Potamon {Geotelphusa) adiatretum , sp. nov. 



This species is very closely related to P. enode, Kingsley, from 

 which it differs chiefly in the bilobed front, and in the restriction 

 of the cervical groove to that portion which bounds the mesogas- 

 tric area posteriorly. 



In an adult female the carapace is only f inch long and |- inch 

 broad. 



From the Kakhyen Hills and Moulmein. 



Subgenus Paratelphusula. 



Potamon {Paratelphusula) fungosum, sp. nov. 



This species comes nearest to P. milne-cdivardsi (Wood-Mason) 

 ( = P. wood-masoni, Rathbun). It has the exposed surface of the 



