1908.] GENUS OF AMPHIPOD CRUSTACEA. 383 



Second Per^eopod. — Femcde (PI. XVI. fig. 8). Very similar to 

 the first peveeopocl, but with the 2nd, 3ixl, 4th, and 5th joints 

 shorter ; the claw is e(|ually as long ; the 2nd joint a little more 

 expanded than in the first perteopod ; the setse on the joints mvich 

 less in number ; claw without denticles. 



Male. 2nd, 3i-d, 4th, and 5th joints as in the female ; 6th and 

 7th longer. 



Setce as in the female. 



The Third Per.^opod is the shortest of all. 



Female (Pl. XVI. fig. 9). The 2nd joint long, broadly oval, 

 anterioi'ly rounded, posterior margin laminarly expanded and 

 produced a little downwards, widest proximally. The 3rd small ; 

 the 4th and 5th practically subequal, the 4th a little dilated 

 posteriorly. The 6th is nearly as long as the 2nd, narrow. Claw 

 moderately curved, nearly two thirds the length of the 6th. 



Setoi. — The 2nd joint has one minute sensory setule indented 

 in the middle of the posterior margin and three in the ante- 

 rior margin, with one large spine at the antei'ior angle. The 

 3rd caiTies one spine on the anteiioi- angle. The 4th has one 

 spine and two or three of the sensor}- setules posteiiorly ; Avith 

 foui' spines on the anterior margin and two at the distal angle. 

 The 5th has three on the anterior margin and two at the angle. 

 The 6th is provided posteriorly with three minute setules and 

 antei'ioi'ly with five spines. The claw is apparently without 

 denticles. 



The branchial vesicle extends to the distal margin of the 5th 

 joint. 



Male. The 2nd joint is as long as the 2nd and 3rd taken 

 together in the female, with the anterior margin lightly concave ; 

 the following joints a little longer, the 6th decidedly so. 



Setce.— A.% in the female, except that the 6th is furnished with 

 a few scale-like spines on the anterior distal angle, and the claw 

 bears four denticles. 



Fourth V^n-EOVOD.— Female (PI. XVI. fig. 6, PI. XVII. fig.l). 

 2nd joint long, lightly concave anteriorly, laminarly expanded 

 posteriorly, and a little produced downwards ; the 3rd small ; 

 the 4th and 6th subequal to each other in length ; the 5th shorter 

 than the 4th or 6th ; 7th half the length of the 6th. 



Setce. — The 2nd joint has one minute sensory setule inserted mid- 

 way on the posterior margin and one spine at the anterior angle. 

 The 3rd carries one at the anterior angle. The 4th has four on 

 the margin, and one large one at the angle posteriorly ; with four 

 at the anterior angle and six on the margin, two of these being- 

 inserted in the same indentation, one a little behind and below 

 the other, an arrangement characteristic of the hinder per^opoda. 

 The 5th carries two of these pairs and two single spines on the 

 anterior margin, and three large spines on the angle, which is 

 produced underneath in a pectinate fringe {cf. PI. XVII. fig. 3). 

 The 6th bears five spines on the anterior margin, the distal half 

 of which is dentate. The claw is provided with two denticles. 



Proc. Zool. Soc— 1908, No. XXV. 25 



