Orchestoidea 529 



side-plate' 5 is extremely wide (from front to back), whereas the basal 

 Joint of peraeopod 8. which is said to be extremely dilated, is in the figure 

 not half as wide as the side-plate). Eyes large, a little reniform (Dana); 

 of moderate size, suboval, slightly navrowed above, wide apart, black (Brandt). 

 Antenna 1 about reaching middle of penultimate Joint of peduncle of antenna 2, 

 flagellum shorter than peduncle, 7- or 8-jointed. Antenna 2 much longer 

 than body; uitimate Joint of peduncle sometimes more than twice as long 

 as penultimate, flagellum longer than peduncle, 35 — 37 (Dana: 20 — 22)-jointed. 

 Gnathopod 1, joints scabrous (Lockington), 5*^ with narrow triangulär sub- 

 apical process of bind margin, 6*^ much shorter thau 5*'^, narrow, without 

 palra, fiuger short. Gnathopod 2, 5*^ Joint small, masked by 4*^^'; 6*^ large, 

 suboval; palm scabrous, moderatoly oblique (Lockington: almost transverse), 

 the centre of it forraing a low oblong tooth or process; finger long and 

 much curved, its apex touching the usual groove in the band. Peraeopods 4 

 and 5 subequal, longer than the rest. Peraeopods 3—5, 2** Joint well 

 expauded; surface of peraeopods scattered over with minute spinules (not 

 mentioued by Brandt), üropod 1, outer ramus without marginal spines 

 (Dana), equally spinulose with the inner one (Stimpson). Telson simple, 

 -cordiform, dorsally longitudinally impressed. L. 22 — 29 mm. 



North-Päcific (North California). Among detritus at high-tide level. 



4. O. pugettensis (Dana) 1853 & 55 Orchestia (Talitrus) p., J. D. Dana in: Ü. 

 S. expl. Exp., ?•. 13ii p. 859; t. 57 f. 3a — d | 1857 0. j^-, Stimpson in: Boston J. nat. 

 Hist., V. a p. 516 i 1862 Orchestoidea p., Bäte, Cat. Amphip. Brit. Mus., p. 3 t. 2 f. 3 

 1893 Orchestia gammarellus (pari.), A. DellaValle in: F. FI. Neapel, i. 20 p. 499. 



Probably the o of 0. californiana (p. 528). Back broad. Head almost 

 <.'ompletely truncate in front. Side-plates 2 — 4 Square, much larger than 

 1"**. 5*'* broad, front lobe about as deep as preceding side-plates, 6*^ strongly 

 produced backward, lower margin ridged. Pleon segment 3, postero-lateral 

 Corners rather sharply quadrate. P]yes rudely subrotund, as far apart as 

 their lougest diameter. Antenna 1 very short, flagellum shorter than peduncle. 

 Antenna 2, uitimate Joint of peduncle nearly twice as long as penultimate, 

 flagellum rather longer than peduncle, of 30 joints, broader than long, with 

 short setules. Gnathopod 1 spinöse, 2*^ Joint slightly curved, channelled in 

 front, ö^^ long, wideuing to a subapical pellucid process, 6*'^ much shorter 

 and narrower thau ö*^'^, but moderately long, slightly curved, without palm 

 but with a slight longitudinal pellucid swelling of bind margin, finger straight. 

 Gnathopod 2, 2'^ Joint very large, a long and broad oval, the membranous 

 expansion fringed with spinules, 4^^ Joint having at hinder apex a little 

 triangulär (seemingly 2-jointed, Dana) process, 5**^ a little longer than 6*^ 

 with membranous bulging of free part, finger small, longitudinal, not reaching 

 produced apex of 6*^ Joint; branchial vesicles small; marsupial plates short, 

 narrow, with a few apical setae. Peraeopods 1 and -2, marsupial plates long, 

 narrow, fringed with long setae. Peraeopod 2, finger abruptly uarrowed 

 midway. Peraeopods 3—5, 2'^ Joint broadly expanded. Peraeopods 4 and 5 

 long, not specially expanded below 2*^ Joint. Üropod 1 long, peduncle and 

 both rami very spinöse (Dana: outer ramus naked). üropod 3, ramus narrow, 

 longer than peduncle. Telson about as long as broad. L. 16 mm. 



North-Pacific (North California). 



5. O. brasiliensis (Dana) 1853 & 55 Orchestia (Talitrus) b., J. D. Dana in: ü. 

 S. expl. Exp., vA'dn p. 857; t. 57 f. 2a — h | 1862 Orchestoidea b., Bäte, Cat. Amphip. 

 Brit. Mus., p. 13 t. 2 f. 4 | 1893 Orchestia gammarellus (part.), A. DellaValle in: F. Fl. 

 Neapel, v. 20 p. 499. 



Das Tierreich. 21. Lief.: T. R. R. Stebbing, Amphipoda I. 34 



