REPORT ON THE AMPHIPODA. 1545 



with a triangular front, the lower side of which forms the striated cutting edge ; the 

 secondary plate on the left mandible nearly as large as the principal plate ; the tooth - 

 like process on the inner surface to the rear of the cutting edge is small and narrow ; 

 the palp set far back has very much of a four-jointed appearance, the small eminence 

 on which it is placed looking like a distinct joint ; of the three regular joints the first is 

 longer and much broader than either of the others, with one margin straight, the other 

 convex ; the second joint is similar in shape ; the third is a good deal longer than the 

 second, slender, distally tapering, much curved. 



First Maxilla?. — These appear to be short, thin in texture, with smooth edges and 

 rounded apex, not nearly reaching the distal end of the inner plate of the maxillipeds. 



Second Maxilla?. — Apparently represented by a pair of smooth oval plates partially 

 overlapping one another, thin in texture, much shorter than those of the first maxilke. 



Maxillipeds. — The inner plate is much longer than broad, longitudinally ridged on 

 the inner surface for some distance from the base upwards ; the distal margin almost 

 straight, having at the centre a pair of little embedded teeth ; the outer plates very 

 much larger than the inner, very broad at the base, the outer edge folding a little 

 inwards, the inner margin sinuous, almost smooth or microscopically pectinate ; there are 

 some minute setules along the outer surface, and a strong longitudinal ridge rises from 

 the base at some distance from the inner margin on the inner surface. 



First Gnathopods. — The side-plates strongly produced forwards, with rounded front 

 apex, and the top of the front margin folded. The first joint not strongly twisted, but 

 sinuous, deeply channelled in front both at the proximal and distal ends, and behind 

 forming a small elbow just below the side-plate ; the much produced front apex of the 

 large wrist is finely pectinate, its chela-forming process has seven teeth on the front 

 and eight on the hind margin besides the apical tooth and many little denticles ; there 

 are nine teeth on the distal half of the hind margin of the hand ; finger less than half the 

 length of the hand. One of the limbs in this specimen is only three-jointed, the third 

 joint being abnormal, oval. 



Second Gnathopods. — Branchial vesicles large, both in this and the following pairs 

 having many lateral pockets. The first joint almost straight, channelled in front, the 

 front margin of the outer surface convex below ; the front of the wrist with the apex 

 not produced downwards, though standing out from the hand ; the chela-forming 

 process more produced than in the first pair, with nine teeth on the front and four on 

 the hind margin, besides the apical tooth ; the hind margin pectinate almost from the 

 base to the four teeth just mentioned ; the hind margin of the hand has nine teeth ; 

 finger much less than half the length of the hand. 



First Perseopods. —Side-plates much wider below than above. First joint bent near 

 the base ; third joint a little wider but scarcely longer than the fourth, the hind margin 

 faintly denticulate ; the fourth similar to the third, more strongly denticulate, the fifth 



(ZOOL. CHALL. EXP. — PART LXVII. — 1888.) Xxx 194 



