REPOET ON THE AMPHIPODA. 1247 



down beside the palmar spine, its inner margin having a few hairs, the dorsal cilinm minute, 

 close to the hinge. 



First Peraeopods attached behind the centre of the segment. The branchial vesicles 

 large, oval. The marsupial plates much larger than the branchial vesicles ; the free margin 

 fringed with setae. The limb consisting of a long slender joint attached by a small hinge, 

 the length about two-thirds, the breadth about one-third, that of the branchial vesicles, 

 the rounded apex canying several setules. 



Second Perseopods attached in front of the centre of the segment, the details similar 

 to those of the preceding pair, except that no setae were perceived on the marsupial plates. 



Third Perwopods attached nearly at the distal end of the segment, with the little 

 smooth-rimmed oval genital-valves projecting from the ventral surface of the segment 

 just in advance of them. The side-plates as usual quite small ; the first joint widening 

 a little distally, with some spines at the apex and one or two spines higher up on the front 

 margin ; the second joint scarcely longer than broad, with some apical spines ; the third 

 joint not quite so long as the first, widening a little distally, with apical spines and a 

 small group of spines near the middle of the front margin ; the fourth joint as long as 

 the first, with spines at four points of the front margin and many round the apex ; the 

 fifth joint about as long as the fourth, with spinules at various points of the hind 

 margin, the front margin smooth for the first fourth of its length or a little more, then 

 forming an advanced point, on which are fixed a pair of rather slender spines apically 

 serrate ; below these the margin is bordered with spines of various lengths and thick- 

 nesses, and setiform spines are set round the sloping sides of the apex ; the finger is 

 strong, curved, capable of reaching the pair of spines on the advanced point of the hand, 

 its inner margin carrying a few hairs. 



Fourth Peraeopods attached quite at the distal end of the segment, similar in arma- 

 ture and general structure to the preceding pair, but the second joint longer than broad, 

 the third joint rather longer than the fourth, the fourth considerably shorter than the 

 first, the fifth longer than the first. 



Fifth Perwopods attached at the distal end of the segment, resembling the preceding 

 pair in structure, but exceeding these and the third pair in size, to some extent in 

 length but especially in breadth. 



Uropods. — Viewed laterally the diminutive pleon presents the appearance of a basal 

 joint, the distal margin of which is (laterally) emarginate, having a pair of small oval 

 appendages attached at the upper end of the emargination, and folding back so as nearly 

 to reach its lower end. There are some minute setules at the apex in these appendages. 



Length. — In a slightly bent position the mounted specimen measures, from the front 

 of the head to the pleon, a quarter of an inch. 



Loccdity. — The label gives " Caprella, 28 fathoms, Arafura Sea." On the glass slide 

 there is the monogram §. 



