6a8 Leptocheirus 



P. A., E. Grube in: Arcb. Natiirg., <:. 321 p. 402 i 1887 Ptilocheiriis h., CheATeux in: 

 Bull. Soc. zool. France, n 12 p. 309 | 1888 Leptocheirus h., T. Stebbing in: Rep. Voy. 

 Challenger, v.29 p. 561 | 1895 L. h., A. O. Walker in: P. Liverp. biol. Soc, v.9 p. 310 | 

 1895 L. Ä., A. 0. Walker in: Ann. nat. Hist., ser. 6 v. 15 p. 4t>9 | 1871 L. püosus (non 

 Zacldaeh 1844!), A. Boeck in: Forh. Selsk. Christian., 1870 p. 230 | 1894 L. p., G. O. 

 Sars, Crust. Norway, v.l p. 555 t. 197 | 1871 Boeckia typica, A.W. Malm in: Öfv. Ak. 

 Förh., V. 27 p. 544 t. 5 f. 1, la— g. 



Body rather stout, somewhat compressed, but back broadly rounded; 

 pleon without teeth. Head, lateral lobes rounded, little prominent. Side- 

 plate 1 very small, acutely quadrate, eovered by the very large, greatly 

 produced, in front broadly rounded 2<^ side-plate; 3*^ and 4*^^ narrowly oblong, 

 deep ; narrow front lobe of ö*'^ not quite so deep, as 4*^. Pleon segment 3, 

 postero-lateral corners rounded, slightly crenulate above. Eyes small, rounded, 

 dark. Autenna 1 not nearly half as long as body; 1^* Joint slightly longer 

 than 2"^ or equal to it, 3*^ half as long as 2*^; flagellum 16— 20-jointed; accessory 

 flagellum 4 — 6 jointed. Antenna 2 rather shorter; ultimate and penultimate 

 joints of peduncle subequal; flagellum 9-jointed. Gnathopod 1, 5*^ Joint 

 not twice as long as 6*^, which is broader distally, with short palm and 

 small finger (Boeck), or: ö**^ (in 9) about as long as 5*^ and scarcely 

 broader, palm somewhat oblique, finger (in figure) matching or scarcely 

 overlapping it (Sars). Gnathopod 2, 5*^ Joint more than twice as long 

 as 6*^, long oval, junction with 6*^ a little oblique, 6*^ tapering; finger 

 Short, nearly straight, setuliferous. Peraeopods 1 and 2, 2^ and 4*^ joints 

 moderately wide, 6^^ long and naiTow, finger shoi-t, slender, scarcely more 

 than 7a äs long as 6*^ Joint. Peraeopod 3, 2^ Joint narrowed distally, front 

 very convex, bind margin very sinuous; 5*^ Joint longer than 4*^ or 6*^; 

 finger very small. Peraeopods 4 and 5 successively longer; 2^ Joint oblong 

 oval and as in peraeopod 3 fringed behind with plumose setae; finger short, 

 bidentate. üropods 1 and 2 unusually sti'ong, especially the 2^, which have 

 Short broad peduncle, rami very stout, each with double row of stout spines. 

 üropod 3 very small, rami a little longer than peduncle, tapering, with 

 lateral spines and apical setae. Telson rather broader than long, with a 

 spine at each lateral angle of the apex. Colour dark grey, with lighter 

 flecks of variüus sizes. L. 8 mm. 



North-Atlantic with adjoining seas (from Norway to France). 



5. L. dellavallei Stebb. 1864 Protomedeia fasciata (non Kreyer 1842!), 

 A. Costa in: Annuario Mus. Napoli, v.2 p. 155 t. 2 f. 8 | 1893 Leptocheirus pilosus (part., 

 non Zaddach 1844 !), A. Della Valle in: F. Fl. Neapel, u20 p.427 t.4 f. 10; 1. 12 f. 1—14 | 

 1899 L. dellavcUlei, T. Stebbing in: Ann. nat. Hist., ser. 7 v.3 p. 350. 



Body rather slender, pleon segment 4 with 2 dorso-lateral teeth and 

 perhaps a median one, all accompanied by spinules. Side-plate 1 with lower 

 front angle produced into a long acute process, length and acuteness a little 

 variable. Side-plate 2 very large, broader than deep, rounded in front. 

 Eyes round. Antenna 1, 1^* Joint stout, 2^ a little louger, 3^ rather over 

 Va as long as 2^; flagellum about 12-jointed; accessoiy flagellum 2-jointed, 

 as long as 1^* Joint of primary. Antenna 2 much shorter, ultimate and 

 penultimate joints of peduncle equal. Gnathopod 1, 5*^ Joint longer than 

 6*^, which is oblong, a little widened near the short ti'uncate palm; finger 

 curved, reaching beyond the palm, with a decurrent spine near the apex. 

 Gnathopod 2 nearly as in L. hirsutimanus (p. 627), but 5*^ and 6*'^ joints 

 rather narrower, 6*^ more than half as long as 5*^. Peraeopods 1 and 2, 6*^ 

 Joint long and slender, finger nearly as long or (Della Valle) even longer. 



