Lafystius, Laphystiopsidae, Laphystiopsis 209 



Back broad, smooth. Head depressed, rostrum tapering to truncate apex, 

 reachiug eud of 1^* Joint of anteuna 1. Side-plates 1 — 3 rounded quadrangular, 

 4^'' much deeper, acutely triangulär below, ö^^^ and 6^'^ with bind lobe acutely 

 produced downward. Pleou segment 3, postero-lateral corners obtusely quadrate, 

 Segments 4 — 6 flattened. Eyes round, prominent, lateral, dark, Antenna 1, 

 1^* Joint longer tban 2*^ or 3^, all stout, flagellum as long as peduncle, 

 tapering, 6 joints witb sensory fascicles. Antenna 2 sb orter, mucb more slender, 

 ultimate Joint of peduncle longer thau penultimate, flagellum ratber longer 

 tban peduncle, 8-jointed. Gnatbopod 1 feeble, almost unarmed, 5^^ Joint 

 sborter tban narrowly oblong 6^^, finger long, weak, nearly membranous. 

 Gnatbopod 2 stouter, 5*^ Joint subequal to nearly quadrangular 6*^, tbe small 

 palm sligbtly produced, mucb overlapped by tbe ratber stout and curved, 

 bideutate finger. Peraeopods 1 — 5, 4^^ Joint ratber wide, not long, finger 

 strong, booked. Peraeopods 1 and 2, 6*^ Joint stout. Peraeopods 3 — 5, 2*^ Joint 

 €val quadrangular, in peraeopod 5 angled at lower bind corner. Uropod 1, 

 rami subequal, uropods 2 and 3, outer ramus sborter tban inner; uropod 3, rami 

 unarmed, ending obtusely. Telson rounded oval. Colour wbite, more or 

 less pellucid. L. 7 mm. 



North-Atlantic and Mediterranean (from the Trondhjemsfjord to the Gulf of 

 Salerno). On various fishes, Raja batis L., Lophius piscator L., Gadus morhua L., 

 Acipenser stiirio L., Galeus galeus (L.). 



15. Farn. Laphystiopsidae 



1899 Laphystiopsidae, T. Stebbing in: Ann. nat. Hist., ser. 7 r. 4 p. 211. 



Body depressed. Head, rostrum broad, not tapering. Side-plates all 

 sballow, 5*'^ the deepest. Eyes rudimentaiy. Antenna 1 slender, louger 

 tban antenna 2, no accessory flagellum. Upper lip apically broad, bilobed. 

 Lower lip witb small inner lobes. Mandible, cutting edge denticulate, 

 arcessoiT plate on left and rigbt, no spine-row, molar weak, conical, palp 

 slender, 3'^ Joint longest. Maxilla 1, inner plate witb 1 seta, outer witb few 

 spines, palp large, 1-jointed. Maxilla 2. inner and outer plates small, subequal, 

 only setose at apex. Maxillipeds, inner plates sbort, outer small, not over- 

 lapping 1*** Joint of 4-jointed palp. Guatbopods 1 and 2 small, simple. 

 Peraeopods 1 — 5 not robust, 2*^ Joint in all somewhat expanded, most in 

 peraeopod 5, wbicb is notably tbe longest. Uropod 3, peduncle very sbort, 

 rami lanceolate. Telson entire. 



Marine. 



1 geuus, 1 species. 



1. Gen. Laphystiopsis 0. Sars 



1893 Laphystiopsis (Sp. un.: L.planifrons), G. 0. Sars, Crust. ISTorway, «;. 1 p.386. 

 Witb tbe characters of tbe family. 

 1 species. 



1. L. planifrons 0. Sars 1893 L.p., G. 0. Sars, Crust. Norway, r. 1 p.386 t.l35. 



Body r^atber slender, depressed anteriorly, segments imbricated. Pleon 

 Segments 3 and 4 witb compressed gibbous dorsal projection, preceded in segment 4 



Das Tierreich. 21. Lief.: T. R. R. Stebbing, Amphipoda I. 14 



