REPORT ON THE AMPHIPODA. 1175 



the first gnathopods; the second joint with a spinule on the hinder apex; the third broad, 

 scarcely longer than broad, with a spinule in the middle of the convex front margin, and 

 a group of unequal spines, the hinder very long, crossing the broad distal margin ; the 

 wrist quite as long as the first joint and rather longer than the hand, narrow, of almost 

 even width throughout, the hinder margin a little crenate, fringed with about twenty-four 

 feathered spines that exceed the length of the joint itself, and having an inner similar 

 row, the feathering of the spines long and close ; the hand narrower than the wrist, 

 almost as long, tapering, with a row of about fourteen long spines along the hind margin, 

 those nearer the apex shorter than those nearer the base, the inner surface also having 

 numerous groups of very long spines which might project on either margin according to 

 circumstances ; the finger about a third of the length of the hand, slender, with the inner 

 margin convex near the base, then very concave, smooth, not running out into a tooth, 

 with cilium and setules as in the first gnathopods. It should be stated that the flexibility 

 of the immensely long spines in these gnathopods would perhaps make it more correct to 

 call them setae than spines. 



First Perseopods. — Side-plates not longer but of more even width than in the 

 preceding pair. Branchial vesicles rather broader than the preceding pair. First joint 

 reaching below the side-plate, packed with three rows of gland-cells, having a few 

 marginal spinules ; the second joint short, with a small spine on the hinder apex ; the 

 third joint large, widening distally, nearly as long as the first joint, with some small 

 spines at two or three points of the hind margin, spinules at three points of the front, 

 and some slender spines on its slightly decurrent apex ; the fourth joint half the length 

 of the third, with spines at the front apex, and at four points of the hind margin ; the 

 fifth joint shorter than the third, much longer and thinner than the fourth, tapering, a 

 little curved, with a slender spine near the top of the convex front, a spine or seta at its 

 apex, and spines at six points of the hind margin ; the finger narrow, more than half the 

 length of the fifth joint, with a long dorsal cilium near the hinge, and an opening in the tip. 



Second Perseopods. — The side-plates rather broader than the preceding pair, tbe hiud 

 margin a little concave. The limb scarcely differs from that of the first perseopods. 



Third Perseopods. — The side-plates with a deep front lobe, having a small spine and 

 spinule near together on the rounded lower margin ; the shallower hind lobe has on its 

 lower margin a strong backward-curved spine, followed at a little distance by a spinule. 

 The branchial vesicles are smaller than in the preceding segment. The first joint broad, 

 longer than broad, the front margin convex, with small spines at intervals, and on the 

 lower part two groups of larger spines, the hind margin tending to concave, slightly 

 serrate, furnished with spinules ; the short second joint with a group of slender feathered 

 spines on the front apex, and a spinule higher up ; the third joint longer than the fourth, 

 with slender spines at three or four points in front, and a stout spine at the apex, the 

 hind margin nearly straight, having at the apex two stout spines, one much larger than 



