of the ^^ Genus " Peneus. 511 



eved Crust. 1853, p. 317; Heller, Crust, .sudl. Europ. 1863, p. 292; 

 Aliers, P. Z. S. 1878, p. 298 ; Boas, Stud. ov. Decapod., Vid. Selsk. 

 Skr. 6 Raskke, nat. o. math. Afd. i. 2, 1880, p. Ibo ; Spence Bate, 

 Ann. & Mag. Nat. Hist. (5) viii. 1881, p. 173, and 'Challenger' 

 Macrura, 1888, p. 229 ; Haswell, Cat. Austral. Crust. 1882, p. 198; 

 S. I. Smith, Proc. U.S. Nat. Mus, viii. 1885, p. 170 ; Ortmann, in 

 Bronn's Thierreich, Malacostraca, pp. 1118-1120; Holmes, Occas. 

 Papers Calif. Acad. Sci. \'n. 19U0, p. 217 ; Kishinouye, Journ. 

 Fisheries Bureau, Tokyo, viii. no. 1 (1900) ; Alcock, Cat. ludiau 

 Deep-sea Crust. 1901, p. 13. 



Rostrum well developed, laterally compressed. Carapace 

 with postal itennular (antennal) and hepatic spines, sometimes 

 with a small postocular (orlntal) tooth or spine, and some- 

 times with a spine (branchiostegal) at or near its antero- 

 inferior angles. The cervical groove is never impressed on the 

 tergum of the carajjace. Abdomen long, with some of its 

 posterior somites compressed and their terga carinated. 



Eyes large. Basal joint of antennular peduncle hollowed 

 dorsally to lodge the eye ; its outer edge terminates in a 

 spine, and from the proximal end of its inner edge there 

 springs a twisted setose scale (antennular scale) ; the 

 antennular flagella are cylindrical and tapering and may be 

 short or long, but are never as long as the body, Antennal 

 scale large and foliaceous, its outer edge is rigid and 

 terminates acutely; antennal flagellum very long. The 

 mandible has a jagged cutting-edge and a broad grinding 

 crown; its palp (endopodite) is large and broadly foliaceous, 

 consisting of two segments, of which the anterior is very 

 much the larger. The endopodite of the maxillule (first 

 maxilla) may be long and 2-, 3-, or 4-jointed, or may be 

 without segmentation and truncated ; that of the maxilla 

 (second) is short. 



The endopodite of the first maxillipeds is slender and 

 5-jointed, tliat of the second and of the third consists of 7 

 segments. The exopodite of the second and third maxilli- 

 peds is very well developed, being curved, compressed, 

 stiffish, and made up, like the flagella of the antennse, of 

 numerous small joints. The third maxillipeds are long and 

 pediform. The first three pairs of legs are chelate, the first 

 pair usually being the shortest and the third pair usually the 

 longest. The last two pairs of legs are monodactylous, 

 Exopodites are usually present on all or all but the last pair 

 of thoracic legs, but are sometimes altogether wanting. 



No podobranchise exist on any of the true legs, and 

 only 07ie arthrobranch — the posterior one — is present on the 

 penultimate legs. 



The abdominal appendages are of moderate length, the 



