A.MPHIPODA. 239 



The wrist of the 1st gnathopods is considerably wider at the distal end than the 

 base of the hand; the latter has 2 or 3 spinas on the posterior margin just 



beyond the widest part. 



Socarnella, n. gen, 



Upper antennae with the 2nd and 3rd joints well developed, and the 1st joint of 

 the flagellum like the succeeding joints. 

 Mandibles as in Amaryllis. 

 First maxillae with a palp. 

 First gnathopod not subchelate. 



Second gnathopod with hand long and widening distally. 

 ( hiter ramus of 3rd uropods without a terminal joint. 

 Telson small, emarginate at the tip. 



Socarnella bonnieri,* n. sp. Plate I., figs. 4. 



One female ; length 5 millims. Reef, Galle, with compound Ascidians (February lfi, 

 1902). Head with the ocular lobe produced ; convex on the upper side. Eyes large, 

 oval, dark, with large crystalline facets. 



Third segment of pleon with the hind margin convex, the lower margin straight, 

 posterior angle rounded (fig. 4. pi. 3 ) ; the 2nd segment has the posterior angle acute. 



First 4 side plates rather deeper than the segments. 



First segment of urns even. 



Upper antennae: 1st joint twice as long as wide, and as long as the 2 succeeding; 

 2nd rather longer than 3rd, which is subequal to the 1st joint of the flagellum. 

 Flagellum setose, 9-jointed ; the 1st joint like the succeeding, but twice as long as 

 the 2nd. Appendage strong, 5-jointed, reaching to the 4th joint of the flagellum. 

 The 1st and 2nd joints of the peduncle are acutely produced below, the 2nd more 

 than the 1st (tig. 4. ant. 1 ). 



Lower an ten life : 2nd joint widening distally, rather longer than the 3rd, the two 

 together about as long as the 7 -jointed flagellum. 



Mandible much as in Amaryllis, the palp placed near the proximal end, the 

 3rd joint about one-third of the 2nd, bent at a right angle (fig. 1. in.). 



First maxillae with a strong 2-jointed palp ; outer plate with about 7 dentate 

 spines; inner plate half as high as the outer, pointed, with 2 or 3 unequal setae at 

 the tip (tig. 4. mx. 1 ). 



Maxillipeds : inner plates reaching beyond the 1st joint of the palp, dentate at 

 the ends, setose on the inner margin ; outer plates broad, reaching the middle of the 

 3rd joint, margins smooth. Dactylus distinctly unguiform, acute (fig. 4. nixp.). 



* I have much pleasure in dedicating this species to Mons. Jules Bonnier, who has contributed so 

 much to a better knowledge of the Amphipoda. 



