1912.] S.Keme& R. B.S.SEwELL: Notes on Decapoda, III. 23 
Except for the customary sexuai 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— 
Sb. 130. = A-V-92e) | 95 7 41 N72". 43( ibe W444. fathoms: ~ One 
female; about 41 mm. in length. Regd. No. 7985. 
Si 270. -rdgit- rE (11° 35" 157" N.; 80°02" 15” BE. +300 fathoms. 
Two males, four females (one ovigerous); 30—48 mm. in 
length. Regd. Nos. #°82=. 
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 IgoI 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 Polycheles iyphlops, 
the type of the genus Polycheles and the first recent species of 
Eryonidea to be described. 
By actual comparison of specimens we have been able to 
convince ourselves that Alcock’s Pentacheles hextit 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 Pentacheles 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 Pentacheles 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 discloses a gradual transition 
in the development of the epipods from large well-developted 
organs, through small, delicate thin ones, to merest rudiments 
ims 
