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



from the front margin. The branchial vesicles and marsupial plates resemble those of 

 the preceding pair. This is also probably true of the joints of the limb, some of which 

 in the preceding pair were damaged or missing. The first joint reaches beyond the side- 

 plate and is rather longer than that of the first perseopods ; the fourth joint shorter than 

 the third, bordered behind with several sets of long setae ; the fifth joint not much longer 

 than the fourth, the upper part of its hind border pectinate and carrying a few setae, the 

 lower part smooth ; the lower front part of this joint adorned with six or seven rows of 

 long setae ; the finger as long as the preceding joint, slightly boat-shaped ; its edges 

 smooth, tipjsed with a little slightly curved nail protected by a boat-shaped cap. 



Third Perseopods. — Side-plates broad and deep, rather broader than deep, the front lobe 

 the larger, both lobes partially fringed with setae ; the branchial vesicle narrowed below. 

 The marsupial plates short. The first joint of the limb much narrower and also shorter 

 than the side-plate ; the wing more expanded above than below, both margins fringed 

 with setae, some very long and densely plumose, some setae also on the inner surface ; the 

 third joint widening a little distally, not decurrent, beset with numerous groups of setae, 

 those on the hind margin long ; the fourth joint shorter than the third or fifth ; the fifth 

 joint similar to that in the second peraeopods, so also the finger, but somewhat shorter. 



Fourth Perseopods. — Side-plates deeper than broad, the lower margin fringed with 

 setae behind. The branchial vesicles bent not far from the base, and thence narrowing 

 downwards. The limb similar in structure and furnishing to those of the preceding pair, 

 but all the joints except the second longer; the fourth joint has distally a little oval- 

 ended process overlapping the following joint behind in one member of the pair of limbs, 

 whether broken off in the other member of this and in the other pairs of peraeopods I 

 cannot say ; while the finger in the third pair is much shorter than the preceding joint, 

 it is in this pair fully as long. 



Fifth Perseofods. — Side-plates much broader than deep, lower margin fringed with 

 short setae. In the Plate the side-plate and the hinder corner of the segment above it 

 are figured with the lettering prp. 5., but in fact the peraeopods themselves were missing. 

 In this figure the hairy nature of the integument is indicated. In the second (much 

 smaller) specimen alluded to above, the first three joints of the fifth per^opod are 

 preserved, the first is very much broader than the corresponding joint in the preceding 

 limb, somewhat ovate, with the upper part much broader than the lower ; the front 

 margin longer than the hinder ; the third joint narrower below than above, very slightly 

 produced behind. 



Pleopods. — Numerous setse upon the peduncles ; the pair of coupling spines (as 

 observed in the smaller specimen) very small and slender, with a terminal hook and one 

 retroverted tooth with its tip upturned ; the cleft spines appear to be four in number ; 

 the joints of the rami numbered ten to twelve in the small specimen, but seemed to be 

 rather more numerous in the larger. 



