58 Hippomedon 



34, Geu. Hippomedon Bocck 



1871 Hippomedon (part.), A. Boeck in: Forh. Selsk. Christian.. 1870 p. 102 1 1872 H., 

 A. Boeck, Skand. Arkt. Ampliip., vA p. 135 | 1890 H., G. 0. Sars, Crust. Xorway, v.l 

 p.55 I 1893 H., J.Bonnier in: Bull. sei. France Belgique, <-.24p.l74 | 1893 H., A. Della 

 Valle in: F. Fl. Xeapel, ».20 p.807 j 1894 H., T. Stebbing in: Bijdr. Dierk., ia7 p. 4 | 

 1888 Platamon (Sp. un. : P.longimanus), T. Stebbing in: Rep. Voy. Challenger, ».29 p.642. 



Side-plates rather narrow. Pleou segment 3, postero-lateral angles 

 sharply upturned. Eyes imperfectly developed. Antenna 1, flagellum not 

 large, 1^* Joint very large, accessory flagellum small. Antenna 2 much longer 

 than antenna 1, flagellum many-jointed; flagellum of antennae 1 and 2 witli 

 calceoli in,c5. Epistome not projecting. Mandible short and strong, molar 

 prominent, powerful, palp elongate, afflxed in front of molar. Maxilla 1, 

 inner plate short, with 2 setae, outer with tlie usual spines, palp expanded 

 distally, carrying numerous spine-teeth. Maxilla 2, plates rather short and 

 broad, the inner fringed on inner margin. Maxillipeds, outer plates fringed 

 with spine-teeth on straight inner margin, generaliy reaching much beyond 

 2*^ Joint of the robust palp. Guathopod 1 slender, 5*^ Joint long, 6*^ oblong 

 ovate, with ill-defined palm, finger slender. Guathopod 2 subchelate. Peraeo- 

 pods slender, except 2*1 Joint of pairs 3 — 5. Branchial vesicles of peraeo- 

 pods 3 and 4 somewhat complex, a small one on peraeopod 5. Uropod 3. 

 rami long, subequal, with marginal spinules, generaliy without conspicuous 

 setae, the outer 2-jointed. Telson oblong, cleft deep, dehiscent, with 1 pair 

 of apical spinules. 



6 species. 



Synopsis of species: 



J Eyes with one conspicuous lens apiece 1. H. holböUi . . . . ]). 58 



- ) Eyes without lenses — 2. 



I Pleon segment 3, lateral processes defined by ii 

 2 j notch 2. H. denticulatus . . p. 59 



l Pleon segment 3, lateral processes without notch — 3. 



J Gnathopod 1, palm confluent with hind margin — 4. 



I Grnathopod 1, palm not confluent (}. H. geelongi . . . . p. 60 



I Pleon segment 3, lateral processes acntely pro- 

 longed 3. H. propinqvus . . p. 59 



"* 1 Pleon segment 3, lateral processes rather short 

 1 and blunt — 5. 



I Cleft of telson scarcely dehiscent 4. H. robustus . . . . p. 59 



) Cleft of telson strongly dehiscent 5. H. longimanus . . p. 60 



1. H. holbÖUi (Kreyer) 1846 Anonyx h., Kreyer in: Naturh. Tidsskr., ser. 2 

 V.2 p.8, 38 J 1846 A. h., Kreyer in: Voy. Nord, Crust. 1. 15 f. 1 a — s | 1866 Lysianassa h., 

 Goes in: Öfv. Ak. Förh,, ».22 p. 520 | 1885 Hippomedon h. var., G. 0. Sars in: Norske 

 Nordhavs-Exp., ».6 Crust. I p.l42 1. 12 f. 2 | 1887.fi. h., H.J. Hansen in: Vid. MeddeL, 

 ser. 4 ».9 p. 63 t. 2 f. 1— Ib | 1890 H. h., H. holb0lli, G. O. Sars, Crust. Norway, ».1 

 p. 58 t. 21 f. 2 I 1893 H. holbölli (pari), A. Della Valle in: F. Fl. Neapel, ».20 p. 808. 



Head, lateral angles not produced. Side-plate 1 scarcely widened below. 

 Pleon segment 3, postero-lateral angles moderately upturned, acute, segment 4 

 with conspicuous carina. Body above and partly on the side very finely 

 reticulate with longitudinal Striae, side-plates and sides of pleon finely granu- 

 late. Eyes at lateral angles of head, with a conspicuous watchglass-shaped 

 lens. Antenna 1, joints of peduncle not produced, flagellum 12-jointed, 

 accessory flagellum 4-jointed. Antenna 2, ultimate Joint of peduncle little longer 



