REPORT ON THE AMPHIPODA. 683 



lobes of the head ; the front edge of its thin plate seems to be sharp, and is very 

 straight. In one specimen there Avas a little tooth in the front part of the rounded top. 



Upper Lip) short, its distal edge densely fringed with short fur. 



Mandibles. — These are very long and naiTOw; the cutting edge has at the top a little 

 pointed tooth, the lower border almost or quite entire ; I was not able to perceive any 

 trace of a secondary plate, though the rudiment of one might have been present 

 notwithstanding, concealed by the folding of the principal plate, but what could be seen 

 of the new mandible in preparation, which is perfectly flat, gave no indication of this ; 

 the spine-row consists of three curved spines not far from the cutting-plate, followed by 

 a long close-set row of short thick cilia, reaching to the small, triangular, ciliate, not 

 dentate, molar tubercle ; at a considerable distance behind this rises the palp, its first 

 joint comparatively long, the long second joint with its lower part thickest, cariying a 

 row of eight or nine pectinate spines at the distal end ; the third joint curved, not twice 

 as long as the first, the two together scarcely equalling the length of the second, with 

 spines on the middle of tlie inner margin and on the apex, and adpressed cilia on the 

 surface. The articular condyle, which in some genera overlaps the base of the palp, is 

 here at an immense distance from it, being just over the three spines of the spine row. 



Loiver Lip much furred round the apex and long inner margins ; the mandibular 

 processes narrow, not much produced. 



First Maxilla}. — Inner plate long, narrow, ciliated, with an almost pointed apex, 

 without any setse in the specimens examined ; outer plate large, the somewhat sloping 

 apical border fringed with eleven spines, of which seven are stout, those near the inner 

 margin especially broad and multidentate, but inserted below the uppermost spines are 

 four slender and curved ones apically forked but not otherwise dentate ; the palp is 

 slender, its second joint apically divided into five or six small teeth, beside which a spine 

 rises from an indent on the outer margin. 



Second Maxilla^.— The inner plate as long as the outer, and broader ; a row of fifteen 

 pectinate spines from the apex some way down its inner margin ; the apical border of 

 the outer plate is crowned with much longer spines which over-arch those of the inner 

 plate. 



Maxillipeds. — Inner plates very long, reaching beyond the middle of the second joint 

 of the palp, inner margins densely clothed with cilia, in the adult hiding the apical 

 outward-sloping margin, which in a young specimen can be seen to possess three minute 

 teeth or prominences indicative of teeth ; the outer plates very large, projecting rather 

 beyond the second joint of the palp, with no sign of teeth or spines on the indentured 

 inner and apical border ; of the setiform spines on the inner border of the third joint 

 the shorter ones have unusually thick accessory threads ; second joint of the palp much 

 longer than the first ; finger very small, much shorter than the third joint, with a slender 

 adpressed denticle lying along the base of the small spiniform nail. 



