1908.] GE^fUS OF AMPHIPOD CRUSTACEA. 389 



cutting-edge obliquely truncate ; no molai*. The 1st joint of the 

 pal20 is very short, twice as broad as long ; 2nd joint long aiid 

 broad, with a series of long stiff bristles commencing at the 

 posterior distal angle and crossing the joint to the anterior 

 margin, where it is continued downwards in a double line for 

 half the length of the margin. These bristles, numbering 50, 

 are closely crowded, and are inserted inside the margin on the 

 outer face ; on the under side there are 5 large stiong ones inset 

 at intervals on the margin. The 3rd joint equals the second in 

 length. This joint is covered with a dense mass of fine trans- 

 pai-ent spines giving it a furred appearance. It is furnished 

 with 15 long, curved, plumose bristles along the anterior margin, 

 inset on the under side, the distal thi-ee forming a distinct group, 

 shorter, more curved, and at wider intervals than the others. 

 At the apex are two bristles set at a different angle from the 

 others and from each other, the upper one the shorter of the two, 

 both with dentate shafts and plumose tips. 



In the young (PI. XYIII. fig. 13) the 1st joint of the palp is 

 longer in proportion, the second joint being only thi'ee times its 

 length, instead of five times as in the adult. The 2nd joint is 

 shorter than the third, with no bristles developed ; the 3rd has 

 the two apical bristles, the distal one of the small group, and the 

 distal one of the long series. 



First Wk^wsl^.— Adult (PI. XYIII. figs. 14 & 15; of. also 

 PI. XIX. fig. 1). With outer plate, elongate, contracted below the 

 apex, and divided at the tip into five large claw-like teeth, four 

 of them much curved ; the fifth is not at the same level but set a 

 little farther down on the inner side, with a small spine at its 

 base on the inner margin, and a tuft of fine setae just below. The 

 falp is small, bi-articulate, set broadside on, the first joint very 

 minute, the second twice as long and tipped with two setules, 

 one longer than the other. The inner plate is very small, not 

 a quarter the length of the outer portion, unarmed, of delicate 

 structure. 



In the young (PI. XIX. figs. 2 & 3) the inner plate and the 

 paljy are much longer in proportion. The outer 'plate is rounded 

 at the apex, the five teeth not being separated as in adult. The 

 palp is bi-articulate, the two joints subequal, the apex tipped with 

 two setules. 



Second Maxilla. — Adult (PL XIX. fig. 4). The two plates 

 almost equal, the inner slightly the shorter, both hollowed under- 

 neath, giving the appearance of much less than their actual 

 breadth. The outer plate carries two minute setules at the tip, 

 one inset at the outer surface and one on the inner, and a few 

 hyaline, sensory setse on the inner margin. The inner plate has 

 the apex obliquely truncate, beset with three setules, the distal 

 one the shortest. This plate also has a few of the hyaline setse. 



In the young (fig. 5) the proportions are the same, the plates 

 being rounded at their apices. 



Maxillipeds. — Adult (PI. XIX. fig. 6). The maxillipeds are 



