532 Orcliestia 



Body rather compressed. Side-plate 1 much smaller than 2'^, b^^ 

 iiearly as deep as 4*^. Pleon segineüt 3, postero-lateral corners (Quadrate. 

 Eyes subrotund or transversely oval, dark, usually nearer together than 

 tlieir width. Antenna 1 reaching end of penultiraate Joint of peduncle of 

 anteuua 2, joints of peduncle subequal in length, flagellum sborter than 

 peduncle, 6- or 7-jointed. Antenna 2 ^/g as long as body or less, penultimate 

 Joint of peduncle ^/^ as long as ultiraate, flagellum subequal to peduncle, 

 20-jointed. Guathopod 1 in d, 5*^ Joint with the subapical pellucid process 

 scabrous, broadly rounded, 6*^^ much sborter, bind margin sinuous, distal 

 pellucid process scabrous, point of finger not reaching its extremity, though 

 extending beyond the genuine palm-margin. Gnathopod 2 in d, 4*^ and 

 5^*^ joints very small, 6*^ very large, piriforra, narrow at the finger-hinge, 

 near to which the long, extremely oblique, sinuous, spinulose palm at least 

 usually forms a small tooth, finger very long and sinuous, its apex over- 

 lapping tlie palm at commencement of short bind margin, although the palm 

 itself ends with the sbort channelling adapted to receive the fiuger-point. 

 Gnathopod 1 in 9 , S*'^ Joint without pellucid process, 6*^ sborter than 5^^, 

 spinöse, oblong, with a small pellucid widening at apex of bind margin, 

 which is considerably overlapped by the rather stout, acute finger. Gnathopod 2 

 in , 2'^ Joint expauded, laminar, narrowing distally, 4*'^ Joint with a distinct, 

 though not much produced, rounded process at apex of bind margin, b^^ 

 produced along much of free part of bind margin, process longitudinally 

 truncate, 6*^ widening to a broadly rounded process which does not extend 

 far beyond the palm proper and apex of finger. Peraeopod 3, 2*^ Joint broadly 

 oval, 4**" and 5^^ rather stout. Peraeopod 4, 2^, 4*^^ and 5*^ joints much 

 longer, 2^ oblong oval. Peraeopod 5, 2'^ Joint much wider than in peraeopod 4, 

 bind margin with lower corner broadly rounded, 4*^ Joint in d triangulär, 

 distally much widened, with apex of bind margin truncate, 5*^ Joint in Ö 

 not longer than broad, immediately from narrow point of attachment widened 

 on both sides beyond the broad distal end of 4*^ Joint, then narrowing to apex 

 which is still much wider than the linear 6*^ Joint; in 9 4*'' and 5*^' joints not 

 at all wider than those of peraeopod 4. Uropod 1, rami considerably sborter 

 than peduncle. üropod 2, rami subequal to peduncle, outer ramus sborter 

 than inner, üropod 3, ramus rather sborter than the stout peduncle. Telson 

 triangulär, fringed with spinules. Colour greenish brown. L. 15 mm. 



Mediterranean; North- Atlantic (France, England, Wales, Ireland). Sometimes 

 considerably beyond high-water mark. 



2. O. gammarellus (Pall.) 1766 Oniscus g., Pallas, Mise, zool., p. 191 t. 14 

 f. 25 I 1791 Gmnmarus g., A. G. Olivier in: Enc. meth., u6 p. 187 | 1793 Cancer g., 

 J. F. W. Herbst, Naturg. Krabben Krebse, v. 2 p. 129 t. 36 f. 2, 3 | 1802 & 03 Oniscus g., 

 Talitrus (part.), Latreille, Hist. Crust. Ins., v.3 p. 39; v.6 p. 300 t. 56 f. 5, 6 | 1872 

 Ch-chestia g., A. Boeck, Skand. Arkt. Amphip., v. 1 p. 102 | 1888 0. g., T. Stebbiug in: 

 Rep. Yoy. Challenger, v. 29 p. 1714 [ 1893 0. g. (part.), A. Della Valle in: F. Fl. Neapel, 

 f.20 p.499 t.2 f. 11; t.l5 f. 1—12, 39-43 | 1808 Cancer (Gammarus) littoreus, Montagu 

 in: Tr. Linn. Soc. London, v.9 p. 96 t. 4 f. 4 | 1812 Astacus l, Pennant, Brit. Zool., 

 ed. 5 v.i p. 32 | 1813/14 Orchestia littorea, Leach in: Edinb. Enc, v.7 p. 402 t. 221 

 f. 6 I 1890 0. l, G. O. Sars, Crust. Norvvay, v. 1 p. 24 1. 10 | 1876 Orchestes l, R. T. 

 Maitland in: Tijdschr. Nederl. dierk. Ver., ». 2 p. 11 j 1840 Chxhestia littoralis, H. Lucas in: 

 Hist. An. artic, Crust. Arach. Myr., p. 225 | 1848 0. euchore, Friedr. Müller in : Ärch. Naturg., 

 V. 14i p. 53 t. 4 I ?1852 0. dispar, J. D. Dana in: P. Amer. Ac, v. 2 p. 204 i ?1853 & 55 

 O.d., J.D.Dana in: U. S. expl. Exp., ».13n p.878; t.59f.6a— m j 1668 0. brevidigitata, 

 Bäte & Westwood, Brit. sess. Crust., v.2 p.497 f. | 1886 0. chilensis (err., non 0. chiliensis 

 Milne Edwards 1840!), G. M. Tliomson & Chilton in: Tr. N. Zealand Inst., v. 18 p. 145. 



