136 Phoxocephalus, Leptophoxus 



P. erythrophthalmus (Catta) 1875 Phoxus e., Catta in: Eev. Sei. nat., v.i 

 p. 163 I 1888 Phoxocephalus e., T. Stebbing in: ßep. Voy. Challenger. i;.29 p. 1717. 



Diifers from P. holböili by the very perfect eyes. 



Mediterranean. 



P. geniculatus (Stimps.) 1855 Phoxus g., Stimpson in: P. Ac. Philad., v.7 

 p. 382 I 1888 Phoxocephalus y., T. Stebbing in: ßep. Voy. Challenger, t?. 29 p. 17I7| 

 1893. P.^., A. DellaValle in: F. Fl. Neapel, u 20 p. 743. 



Rostrum long, acute. Eyes white. Antenna 1, flagellum and accessory flagellum 

 equal, 10-jointed. Peraeopods 1 and 2, 4th and 5tb joints dilated. Uropod 3, rami 

 unequal, outer long, 3-jointed. Colour white. L. 6 mm. 



North-Pacific (Japan). 



P. obtusus (Stimps.) 1855 Phoxus o., Stimpson in: P. Ac. Philad., v.7 p. 382| 

 1888 Phoxocephalus 0., T. Stebbing in: ßep. Voy. Challenger, ü. 29 p. 1717. 



L. 6 mm. 



North-Pacific (Japan). 



P. Simplex (Bäte) 1857 Phoxus kröyerii (non P. kroyeri Stimpson 1853!), 

 Bäte in: Ann. nat. Hist., ser. 2 u 19 p. 140 | 1857 P. simplex, Bäte in: Ann. nat. Hist., 

 ser. 2 17.20 p. 525 | 1888 Phoxocephalus s., T. Stebbing in: ßep. Voy. Challenger, «?. 29 

 p. 1717 I 1893 P. s., A. DellaValle in: F. Fl. Neapel, v.20 p. 743 | 1896 P. s., A. O. 

 Walker in: Ann. nat. Hist., ser. 6 v. 18 p. 157. 



Plymouth Sound. 



2. Gen. Leptophoxus 0. Sars 



1891 Leptophoxus (Sp. un. : L. falcatus), G. O. Sars, Crust. Norway, v. 1 p. 146. 



Body luuch compressed. Hood slightly carinate aod deflexed at apex. 

 Side-plates with a few simple setae on lower margin, 4*^ broad, 5**^ with 

 hinder lobe subtruncate. Antenna 1 much smaller than antenna 2. Antenna 2, 

 peduncle stout, flagellum in Q short, in ö long and slender. Mandible, cutting- 

 plates, spine-row and molar feebly developed, 2*^ and 3<^ joints of palp 

 expanded. Maxillae 1 and 2 about as in Phoxocephalus (p. 134). Maxillipeds, 

 inner plates very small, acuminate, 3"^ Joint of palp strongly produced at 

 outer apex. Gnathopods 1 and 2, 6*^ Joint nearly quadrangular, that of gnatho- 

 pod 2 much the larger. Peraeopod 3, 2^ Joint much expanded. Peraeopod 4, 

 except 2^ Joint, very slender., Peraeopod 5, 2^ Joint large and clypeiform. 

 üropod 3 alike in ö and Q , inner ramus very small, spiniform, outer 

 slender with spines but no setae. Telson as in Phoxocephalus. 



1 species. 



1. L. falcatus (O. Sars) 1871 Phoxus simplex (err., non Bäte 1857 !), A. Boeck 

 in: Forh. Selsk. Christian., 1870 p. 135 [ 1876 P.S., A. Boeck, Skand. Arkt. Amphip., 

 V.2 p.217 t.8 f. 3 I 1882 P. falcatus, G. 0. Sars in: Forh. Selsk. Christian., nr. 18 p.84 | 

 1888 Phoxocephalus f., T. Stebbing in: ßep. Voy. Challenger, v.29 p. 1717 | 1893 P. f., 

 A. DellaValle in: F. Fl. Neapel, 17.20 p. 739 t. 60 f. 15, 16 | 1891 Leptophoxus f., G. 0. 

 Sars, Crust." I^orway, v. 1 p. 147 t. 50. 



Body very slender, especially in ö. Apex of hood hook-like. , Side- 

 plates 1 — 3 each with 3 small setae at lower bind corner, 1^* expanded 

 below, 4*** as broad as deep, almost rectangular below the emargination. 

 Pleon Segment 3, postero-lateral angles obtuse. Eyes wanting. Antenna 1, 

 1^* Joint thick, much longer than 2"^ and 3^ combined, flagellum 5-, accessory 



