GAMMARIDEAN AMPHIPODA 185 



Type-locality.— Station 7358, 27°35'45" N, 115°08'30'' W, 1095- 

 1205 m, Apr. 21, 1961. 



Material.— Stations 7234 (2), 7358 (6). 



RELATioNSHir. — Syrrhoites silex appears to have close affinities with 

 S. sorpresa (J. L. Barnard, 1962a) but differs by its smaller dorsal 

 segmental teeth. It differs from S. dulcis, new species, in the more 

 distinct teeth of pereonites 5-7, by the shallower extent of pleonal epi- 

 meron 3, and the occurrence of its tooth at the normal posteroventral 

 corner instead of on the beveled posterior margin, by the stouter gnath- 

 opods and the stouter second articles of pereopods 3-5. 



This species differs from S. tnix, new species, by the stouter gnatho- 

 pod 1, the distinct teeth of pereonites 5-7, the presence of a tooth on 

 pleonal epimeron 3, and the narrower second articles of pereopods 

 3-5. 



The mouthparts of S. silex are generally like those of S. serrata 

 (Sars, 1895, pi. 137) except for the mandibular palp shown herein 

 and the mediodistal corner of the inner plate of the maxilliped and 

 palp articles 3 and 4 of the maxilliped. The lower lip is like that of 

 S. trux^ new species. Biarticulation on the outer ramus of uropod 3 

 is unclear. 



DisTRiBunoN. — Middle Baja California, 842-1095 m. 



Syrrhoites trux, new species 



Figures 90, 91 



Diagnosis or female. — Eostrum long, thick, slightly curved down- 

 wards; lateral cephalic lobe extended forward moderately, broadly 

 truncated, anteroventral corner rounded-quadrate; antennae slender, 

 antenna 2 not elongated, articles 1, 2, and 3 subequal in length to each 

 other, mediodistal end of article 1 with retroverted cusp, accessory 

 flagellum biarticulate, article 2 very short; gnathopods slender, elon- 

 gated; anteroventral corner of coxa 1 rounded-subacute, anterior edge 

 strongly concave, posteroventral corner of coxa 3 rounded-quadrate, 

 posterior margin scarcely excavate, coxa 4 with moderately oblique 

 ventral edge, posteroventral corner subacute, protruding moderately ; 

 pereopods 1 and 2 with strongly setose posterior margins of articles 5 

 and 6 ; article 2 of pereopod 5 of medium expansion, ovate, posterior, 

 and ventral margins merging, rounded posteroventrally and scarcely 

 extended downward, posterior serrations of medium size ; dorsal carina 

 essentially commencing on pleonite 1, pleonites 1 and 2 with elevated 

 subquadrate posterodorsal corners, pleonite 3 with long, thick, acutely 

 tapering tooth, pleonite 4 with small, slightly erect, acute tooth, pleo- 

 nite 5 with slender, horizontal, acute tooth; pleonite 4 with tliin, 

 acute posterolateral process above insertion of uropod 1 ; pleonal epi- 



