BXPIvANATION OF PlyATE XVIII. 



Potamon {Potamiscus) aborense, sp. nov. 



Fig. 4. — Right half of the carapace in dorsal view, X 2|. 

 ,, 5. — Abdomen of the same specimen. 



Potamon {Potamiscus) sikkimense, Rathbun. 



,, 6. — Abdomen of the variety described by Alcock from Nepal. 



,, 7. — Abdomen of a typical specimen. 



„ 8. — Left half of the carapace of a typical specimen in dorsal 

 view, X 3. 



Potamon {Potamiscus) obliteratum, sp. nov. 



,, 9. — Right half of the carapace in dorsal view, X 2. 

 ,, ga.— Third maxillipede. 



Potamon {Geotelphusa) adiatretum, Alcock. 



,, 10. — Left half of the carapace in front view, X 4. 

 „ II. — -Chela and carpus in lateral view. 

 ,, 12. — Carpus viewed dorso-laterally. 



Potamon {Geotelphusa) adiatretum var. lophocarpus, nov. 



j^ 13. — Chela and carpus in lateral view. 

 ,, 14. — Carpus viewed dorso-laterally. 



Potamon {Geotelphusa) superciliosum, sp. nov. 



,, 15. — Right half of the carapace in front view, X 2. 



,, 16. — Carapace in dorsal view, nat. size. 



,, 17. — Chela and carpus of the same specimen, a male, nat. 

 size. 



„ 18. — Carpus viewed dorso-laterally, nat. size. 



