1222 THE VOYAGE OF H.M.S. CHALLENGER. 



wrist ; the third joint much shorter than the second, flask-like, with the bulb at the 

 distal end ; the wrist much longer than the hand, with numerous setae on and near both 

 margins; the hand not so long as the second joint, an elongate oval, distally sharpened 

 so as to form a little blunt palm process from which a setulc projects, and against which 

 lies the minute finger with its strongly bent tip, forming a microscopic chela ; the sides 

 of the hand are furred with numerous tufts of setae, and at the distal end of the front 

 margin there are the spines usual in the Lysianassidse overarching the finger. These spines 

 were damaged, so that the pectination which might be expected could not be observed. 



First Perseopods. — Side-plates broader and deeper than the preceding pair, the hind 

 margin slightly concave. The first joint attached considerably above the centre, not 

 nearly reaching the lower border of the side-plate, widening a little from the base ; the 

 second joint short, the third distally widened, longer than the fourth, the front apex a 

 little produced downwards ; the fourth joint abruptly narrower than the third, at the 

 hinder apex of which it is attached, slightly curved, with three spinules on the concave 

 hind margin ; the fifth joint a little curved, subequal in length to the third, with a 

 spinule at the hinder apex ; the finger more than half the length of the fifth joint. 



Second Perseopods. — The side-plates rather deeper and immensely broader than the 

 preceding pair, the excavation behind being about half the depth, and more than half the 

 breadth of the plate, the hind margin below the excavation rounded. The limb very 

 similar to the preceding pair, the third joint scarcely so much expanded distally, the fourth 

 with a single spinule on the hind margin, the finger rather stouter and much shorter. 



Third Perseopods. — Side-plates with the hind lobe deeper than the front, the breadth 

 slightly greater than the depth of the hind lobe. The marsupial plates very narrow, 

 with two apical setae. Marsupial plates were not observed attached to any of the other 

 limbs. One pair of oval branchial vesicles was seen, but it was not ascertained how 

 many more pairs there were. First joint attached just above the distal margin of the 

 front lobe of the side-plate, a little wider but not longer than the first joint in the 

 preceding peraeopods, with a pair of apical spinules on the nearly straight front margin, 

 and a row of three a little higher up, the hind margin convex ; the second joint short, 

 with a few spinules on the front margin ; the third joint longer and much more dilated 

 than in the preceding peraeopods, with four spinules on the front and three on the much 

 bowed hind margin, besides one or two at each apex ; the hinder apex acute, completely 

 overlapping the narrow fourth joint, which has a spinule at the middle of the front 

 margin and two at its apex ; the fifth joint longer than the fourth, similarly armed, 

 shorter than the corresponding joint in the preceding peraeopods ; the finger rather more 

 than half the length of the fifth joint ; the nail small. 



Fourth Perseopods. — The side-plates much deeper than broad, the margins nearly 

 parallel, the hinder longer than the front. The first joint wider than the side-plate, 

 rather longer than broad, the front margin convex, with some spinules along the lower 



