REPORT ON THE AMPHIPODA. 1275 



those of the inner plate, the distal margin truncate and having a blunt tooth at each end, 

 each tooth having beside it a comparatively long spine. 



MaxilUpeds. — The inner plate is very much narrower and shorter than the outer ; 

 the outer plates have the straight inner edges scarcely at all dehiscent, the adjacent 

 ridge of the inner surface armed with a few small spinules, the outer edge convex, very 

 lightly furred ; the distal half in these plates is much narrower than the proximal, each 

 ending in a narrowly rounded apex. 



First Gnathopods. — The side-plates shallow, broader than deep. The first joint 

 almost entirely free from the side-plate, evenly broad throughout except at the extrem- 

 ities, with one or two setules near the apex behind ; the second joint short, the surface 

 speckled with tiny spicules, the hinder apex having some small curved spines ; the third 

 joint, very little longer than the second, with a pointed apex lying against the wrist, the 

 hinder surface furred with spicules ; the wrist not so long or so broad as the first joint, 

 but broader and much longer than the hand, widening a little distally, the hind margin 

 fringed w T ith very slender spines, of which there are some also along the surface and at 

 the front apex ; the hand narrow, without palm, having the front margin gently convex, 

 the hinder nearly straight, scabrous, both fringed with slender spines, those on and 

 adjoining the hind margin more numerous than those in front, the surface also carrying 

 many groups of spines ; a slender, nearly straight finger, slightly pectinate on the inner 

 margin, is attached between the two front slightly produced and rounded apices, and in 

 length about equals half the hand. 



Second Gnathopods. — Side-plates a little broader than the preceding pair. Branchial 

 vesicles seemingly about as long as the first joint, widening below. The limb similar in 

 general character to the preceding, the first joint a little longer, with a few setules on 

 the hind margin ; the second and third a little thinner and less scabrous, with slender 

 spines near the hinder apex, the wrist shorter and with fewer spines, the hand longer so 

 as to be nearly as long as the wrist, also with fewer spines and a somewhat less breadth ; 

 the finger not quite half the length of the hand. 



First Perseopods. — The side-plates shallow. The first joint as in the preceding 

 pairs ; the second joint considerably longer than broad, widening from a narrow neck ; 

 the third joint a little shorter than the fourth, a little longer than the fifth ; the fourth 

 as broad as the third, but much broader than the fifth ; the fifth narrow, broadest near 

 the base ; the finger very slender, slightly curved, not quite half the length of the 

 fifth joint ; the armature of the limb very slight, the hind margin of the third, fourth, and 

 fifth joints, and of the finger at its upper half, being faintly pectinate. 



Second Perseopods scarcely differing from the first, but having the third and fourth 

 joints a little longer. 



Third Perseopods. — The side-plates rather deeper than the preceding pail-, 

 narrowly produced both before and behind and carinate. The first joint of great 



