REPORT ON THE AMPHIPODA. 1535 



Second Gnathopods. — Side-plates tending to oblong, but broader above than below. 

 Branchial vesicles longer and much broader than the first joint, with the usual lateral 

 accessory inflations. The first joint not dilated distally, the front margin tending to 

 convex ; the second joint as broad as long ; the third larger than in the first gnathopods, 

 its front margin considerably longer than that of the wrist, the hinder not quite so long 

 as that of the wrist, the rounded apices finely pectinate, the front one being the broader, 

 the hinder the more strongly pectinate ; the wrist, which is widest at its junction with 

 the hand, is produced behind in a rounded process about half the length of the hand ; 

 the hind margin is pectinate, very finely at first, but more boldly as the pectination 

 approaches and passes round the process ; the hand as in the first gnathopods, but a little 

 broader at the base ; the finger is scarcely so long as in the preceding pair. 



First Perseopods.— The side-plates a little less regular than in the preceding pair ; 

 the branchial vesicles similar ; the first joint rather longer, with both margins very 

 slightly convex ; the second joint rather longer than broad ; the third joint decidedly 

 broader and a little longer than the fourth, narrowing distally to a very slight extent, 

 the rounded corners of the distal margin finely pectinate ; the fourth joint narrowing 

 a little distally, wider than, but scarcely so long as, the fifth joint, which narrows a good 

 deal distally ; the finger is slender, curved, acute, not a third the length of the 

 fifth joint. The limb figured in the Plate does not agree with the above proportions, 

 but was probably abnormal. 



Second Perseopods similar to the first, but with the joints a little longer, the fourth 

 as long as the third, the finger scarcely one-fourth the length of the fifth joint. 



Tliird Perseopods. — Side-plates broader than deep, both lobes squared, the hinder 

 one the larger ; the triangular tooth-like process on the inner side has its lower margin 

 convex. Branchial vesicles much broader above than below. The first joint oval, with 

 a very regular hind margin, the front rather less so ; the second joint short, some little 

 way from the distal end of the first ; the third joint subequal in length to the fourth, 

 the two together not reaching back to the base of the first, each with closely pectinate 

 front margin ; the fifth joint narrow, a little curved, rather longer than the fourth, its 

 front margin with the fine pectination oblique, not standing out as in the two preceding 

 joints, the apex pectinate ; the finger very small and slender. 



Fourth Perseopods. — Side-plates not broader than deep, deeper behind than in front. 

 Branchial vesicles with a second lobe above, the larger front division very much narrowed 

 below. The first joint a little longer than that of the third perseopods, its upper half a 

 little broader than that at the centre, but narrowing rapidly to the apex, the front margin 

 almost straight, tending rather to concave than convex except at the two ends, the hind 

 margin at first convex, then oblique ; the distal margin is broken by the short longitudinal 

 slit, behind which the joint forms an almost pointed apex, while in front it carries on 

 the inner surface a blunt process, and below this a pointed process, reaching together 



