514 Dr. A. Alcock — A Revision 



Epipodites present on all but tlie last two thoracic ap- 

 pendages ; pleurobranchiae present on the six posterior 

 thoracic somites. 



Andricum symmetrical, simple, pod-shaped; it consists of 

 two lobes finely interlocking all along their anterior border, 

 and capable of loose apposition in more or less of their 

 posterior border, the opposed faces being concave. 



The dactylus of the third maxillipeds often shows modifica- 

 tions of a secondary sexual nature in the adult male. 



The branchial formula is as follows : — 



Podo- Artliro- Pleuro- 



Somite. branchite. branchiae. bianchife. Total. 



VII ep. 1 (small) . . = ep. + l 



VIII ep. + l 2 .. = ep.+3 



IX ep. 2 1 = ep-l-3 



X ep. 2 1 = ep. + ;) 



XI ep. 2 1 = ep.+3 



XII ep. 2 ] = ep.+3 



XIII 1 1 = 2 



XIV .. 1 = 1 



Total 6 ep. + l 12 6 = 6ep. + 19 



In addition to the Indian forms hereafter specified, I have 

 examined the following species: — P. caramote, P. japonicus, 

 P. australiensis, P. latisulcatus, P. braslUensis, P. setifer, 

 P. stylirostris. 



List of the Species o/Pexeus [sensu restricto). 



I. Antennular Jlagella extremely short; usually a postocular (as well as 

 a postantennular) spine and crest on the antei-ior part of the carapace. 



1. Peneus caramote (Risso), Milne-Edwards, Hist. Nat. Crust, ii. p. 413 



et syn. ( = P. trisulcotus, Leach, Tr. Linn. Soc. xi. 1815, p. 347.) — 

 Mediterranean, W. Africa, England (St. George's Channel). 



2. Peneus canalicuhtus (Oliv.), Milne-Edwards, op. cit. p. 414. (= P. mar- 



.^m«^w*-, Paiidall, Journ. Ac. Nat. Sci. Philad. 1839, p. ] 46, and 

 ? P. plebejiis, Hess, Arch. f. Naturges. xxxi. i. I860, p. 168, pi. vii. 

 fig. 19.) — Indo-Pacific from Red Sea and E. coast of Africa to 

 Sandwich Is. ; also W. coast of Africa. 



3. Peneus canallculatus, var. australiensis, Spence Bate, 'Challenger' 



Macnua, p. 248, pi. xxxii. fig. 3. 



4. Peneus canaliculatus, var. japonicus, Spence Bate, op. cit. p. 245, 



pl. xxxi., pi. xxxii. fig. 4, pi. xxxvii. tig. 2. 



5. Peneus brevirostris, Kingsley, Proc. Ac. Nat. Sci. Philad. (1878) 1879, 



p. 98. (According to Miers doubtfully distinct from P. canalicu- 

 latus.) — W. coast of Nicaragua. 



6. Peneus calif orniensis, Holmes, Occasional Papers Calif. Acad. Sci. vii. 



1900, p. 218. (A doubtful species, originallj identified by Holmes 

 with P. canaliculatus.) — California. 



