REPORT ON THE AMPHIPODA. 1487 



margin of the wrist there are four little spinules on the surface. The gland-cells as in the 

 first pair. 



First Perasopods. — Side-plates, branchial vesicles, and first joint of the limb similar 

 to those of the second gnathopods, but larger. Gland-cells conspicuous in the first and 

 third joints ; the second joint longer than broad ; the third joint broader and longer than 

 the fourth, its front margin very convex, the hinder smooth and almost straight ; the 

 fourth joint similar in shape ; the fifth joint longer than the fourth, shorter than the 

 third, slender, tapering, slightly curved, like the other joints quite smooth ; the finger 

 very small, curved, acute. 



Second Per&opods similar to the first, but with the third, fourth, and fifth joints 

 decidedly longer, and the hind margin of the fifth joint finely pectinate. 



Third Perasopods. — The side-plates much narrower below than near the base, having 

 a round-ended backwardly directed lobe projecting from the inner surface just above the 

 attachment of the limb. The first joint large, elongate oval with flattened sides, sub- 

 equal in length to the four following joints together, the front margin descending below 

 the hinder one, the hexagonal markings very conspicuous over the whole surface both of 

 this and the following joints ; the second joint rather longer than broad, partly embedded 

 in the distal end of the first joint ; the third joint slightly shorter and stouter than the 

 fourth ; the fourth finely pectinate along the front margin and more conspicuously 

 round the front part of the apical margin ; the fifth joint straight, tapering, not longer 

 than the third, with the front margin finely pectinate ; finger missing. 



Fourth Perieopods. — The side-plates deeper behind than in front, the front margin 

 nearly straight, the hinder convex. The first joint larger than in the preceding pair, two 

 or three times as long as the rest of the limb, the front margin convex near the base and at 

 the lower corner, the long intermediate part nearly straight, the hind margin irregularly 

 convex ; facing the hind margin in its upper half is a longitudinal curved slit, the half 

 of an oval in shape, with a transverse or oblique slit at either end ; below this there is 

 a hind margin of the inner surface running parallel to that of the outer, and below this 

 an obbque sinuous fold of the inner surface a little above the rounded hinder apex ; just 

 above this fold is the short second joint, which with part of the next is covered by 

 the first joint ; the third is much longer than the three following joints together, the 

 front margin to the end of the almost acute produced apex being pectinate with slightly 

 retroverted teeth ; the fourth joint which is narrower is similarly armed, and has the 

 front margin rather longer than the hinder ; the fifth joint is dwindled, attached at 

 about the middle of the oblique apex of the preceding joint, not being a third either of 

 the length or breadth of that joint ; there is a minute curved blunt finger to correspond. 



Fifth Perasopods. — No upper boundary of the side-plates could be perceived. The 

 first joint long, slender, curved, narrowest at either extremity, four or five times as long 

 as all the feeble remaining joints together, the front margin concave, the hinder convex, 



