1912.] S. Kemp & R. B. S. Sewell : Notes on Decapoda, III. 23 



Except for the customary sexual distinctions in the second 

 pair of pleopods and in the outer ramus of the antennular 

 peduncle, the specimens closely resemble the females described 

 by Alcock ; we would note, however, that in both sexes there 

 are very frequently two or three spines on each carina of the 

 sixth abdominal somite in addition to the terminal one. 



Two other samples of this species, hitherto unrecorded, are 

 preserved in the Indian Museum — 



St. 136. 4-V-92. 15° 41' N., 72° 43' E. 444 fathoms. One 

 female ; about 41 mm. in length. Regd. No. ^%^. 



St. 279, i8-iii-ii. 11° 35" 15" N., 80° 02" 15" E. 300 fathoms. 

 Two males, four females (one ovigerous) ; 30—48 mm. in 

 length. Regd. Nos. ^^i^-^. 



DECAPODA REPTANTIA. 



Tribe Eryonidea. 

 Family ERYONIDAE. 

 Genus POLYCHELES, Heller. 



The majority of recent authors have not followed Spence 

 Bate in the recognition of distinct genera, Polycheles and Penta- 

 cheles, and there can be no doubt that, as many subsequent 

 authors have shown , the distinctions employed in the ' Challenger ' 

 Report are untenable. 



Alcock, however, in 1901 again recognized the two separate 

 genera, distinguishing them by the characters afforded by the 

 epipodites of the third maxillipeds and of the peraeopods. Un- 

 fortunately at the date when he was writing, little was known 

 as regards these structures in the case of Polvchelcs iyplilops 

 the type of the genus Polvchties and the first recent species of 

 Eryonidea to l)e described. 



B}' actual comparison of specimens we have been able to 

 convince ourselves that Alcock 's Pcntacheles hextii must be 

 regarded as a synonym of Polycheles typhlops and this, if two 

 genera are to be recognized, necessitates the transposition of the 

 names Polycheles and Pcntacheles as applied by him. In P. 

 typhlops the epipod at the base of the third maxilliped is small ; 

 but the distinction in this respect between the genera seems of 

 little moment. More important by far is the condition of the 

 epipods at the base of the peraeopods and in P. typhlops these 

 structures agree precisely with those of specimens which Alcock 

 referred to Pentachclcs and with the account contained in his 

 description of that genus. 



Faxon, however, in 1895 (p. 118) remarks that '' an examina- 

 tion of a large number of species disclo.ses a gradual transition 

 in the development of the epipods from large well-developted 

 organs, through small, delicate thin ones, to merest rudiments 



