REPORT ON THE AMPHIPODA. 833 



the hiucl margin, some of them very long, and a group at the apex in front ; the fourth 

 joint subequal in length to the fifth, a little expanded downwards, with spine-like setae 

 near the apex behind ; the fifth joint similarly armed, of almost even width throughout ; 

 the finger shorter than the fifth joint, slender, tapering. 



Second Peraeopods. — Side-plates broad, squared, scarcely deeper than broad, the 

 excavation behind not deep. Branchial vesicles longer than the side-plates. Marsupial 

 plates as in the preceding pair. The first joint of the limb not quite reaching tlie end 

 of the side-plate, the setae at the end of the fourth joint exceeding the length of the fifth 

 and sixth joints combined ; the limb in general not diflfering from the preceding. 



Third Perseopods. — The front lobe of the side-plate with the front margin flattened, 

 the convex lower margin somewhat serrate, carrying setae. The marsupial plates a little 

 widened distally, there carrying four long setae and one short one. The first joint longer 

 than broad, widened below, the hind margin nearly straight and almost naked, the front 

 convex, with two long setae near the centre and two spines lower down, at the apex a seta 

 and two long spines ; the second joint short, with one spine ; the third broad at the centre, 

 decurrent behind, carrying groups of strong spines in two deep serrations of the front 

 margin, and two of the hind margin, the apex of which is truncate, and bordered with 

 five unequal spines attended by two small setae, an additional group of spines being placed 

 on the surface at the base of the decurrent part ; the fourth joint is longer and narrower 

 than the third, and carries groups of spines, one on the margin and one on the apex 

 before and behind, many of the spines here and elsewhere being notched at the tip besides 

 carrying an accessory thread ; the fifth joint short and slender, with spines at the apex ; 

 the finger missing, evidently broken ofi". 



Fourth Perseopods. — Side-plates broader than deep, with some set« on the lower 

 margin behind, this margin curving upwards to an angle. The first joint oval, with some 

 setae on the upper part of the front margin and spines at its apex ; the hind margin 

 smooth ; the second joint small, with a spine in front ; the third joint greatly expanded, 

 so as distally to exceed the width of the first joint ; it has four groups of spines and setae 

 on the hind margin, one on the front, and three distal groups as in the preceding pair ; 

 the fourth joint is also of great breadth, narrowing distally, carrying three groups of 

 spines and setae in the deep serrations of the front, and two in those of the hind margin, 

 besides two large groups at the apex ; the fifth joint is narrow, as long as the third, rather 

 shorter than the fourth, with two sets of spines in the serrations of each margin, and two 

 apical groups ; the finger is straight, slender, tapering, more than half the length of the 

 fifth joint, with pectinate edges. In many of the groups of spines there is one with the 

 upper part tapering, pectinate on both edges, while others have the notched end without 

 pectination, and some are slightly plumose. 



Fifth PeriBopods. — Side-plates small, the segment with its postero-lateral angle 

 acute, carrying a cilium in a little notch below the angle. The first joint appears to be 



(ZOOL. CHALL. ESP. PART LXVII. 1887.) XxX 105 



