REPOttT ON THE AMPHIPODA. 1321 



lower lip and the distal emargination of the upper lip come into view, with the cutting 

 edges and molar tubercles of the mandibles lying under and between them ; the trunks 

 of the mandibles being partially released from their attachment are here more widely 

 displayed than in the upper figure. 



Upper Lip broader than the epistome, broader than deep, smooth-edged, unsym- 

 metrically bilobed, the cleft in the distal margin being narrow and not very deep. 



Mandibles. — The cutting edge narrow, with nine teeth on the right mandible and 

 perhaps one or two more on the left ; the lowest tooth in each recedes behind the line of 

 the others, and behind and below it there is a tuft of cilia-like spines, the, lower margin 

 beyond being smooth ; the secondary plate on the left mandible is quite narrow at the 

 base, but widens out till its distal margin, which is cut into thirteen denticles, is about 

 as wide as that of the principal plate, the edges so closely overlapping that it is not 

 very easy to distinguish the teeth of the one from those of the other ; the molar 

 tubercle on each mandible large, with a very long, straight front edge, which is closely 

 ciliated, and carries a row of small projecting teeth or spine-teeth, not epiite closely set, 

 more than fifty in number, besides several other rows of smaller teeth ; the trunk of 

 the mandible is large, the lower margin forming an obtuse angle at some distance behind 

 the molar tubercle, while some distance further back the extremity of the mandibles 

 forms an acute angle, the long comparatively straight upper margin having in advance 

 of the centre a small triangular process with a broad base extending backwards, this 

 process possibly representing a rudiment of the palp. 



Lower Lip. — The outer and inner lobes coalesced, though distinguished by a strong- 

 ridge or suture, both dehiscent, the inner a little less than the outer, the inner margin 

 of the outer lobes slightly hairy, that of the inner lobes strongly ciliated; the mandibular 

 processes apically rounded, not divergent. 



First Maxillee. — The inner plate appears to be a smooth thin exjxansion surmounting 

 the short first joint, but scarcely prominent beyond the inner margin of the long 

 second joint ; the outer plate short and broad ; some way up on its sinuous inner margin 

 a series of setiform spines begins, which is continuous right round the very broad 

 distal margin, but there is also a series of stronger spines, on the distal part of the inner 

 margin three that are rather narrow, followed by six stronger, a weak one, a strong one, 

 two weak ones, and then a mixed group, in which there are three or four especially 

 large and strong ; the single-jointed palp is not so broad as the outer plate, but is 

 rather longer, with some very minute spine-teeth on the inner margin, the apical margin 

 being cut into many very acute little teeth, some still smaller teeth descending a part 

 of the convex outer margin. 



Second Maxillse. — Basal part broad, beyond the centre abruptly contracting on the 

 inner side, the inner margin then running smoothly and almost straight to the apex, 

 but within this margin, before the apex is reached, there is a small linear projection, 



(ZOOL. CHALL. EXP. PART LXVII. — 1888.) Xxx 1G6 



