866 



THE VOYAGE OF H.M.S. CHALLENGER. 



as the first joint of the peduncle, second and third joints cylindrical and subequal in 

 length, being about half the length of the first joint, flagella subequal in length, upper 

 stout at the base. 



Second pair of antennae having a scaphocerite that is half as long again as the 

 peduncle of the first pair, narrow and lanceolate ; flagellum long and slender. 



Anterior two pairs of pereiopoda having the chelae long and narrow, the second 

 pair having the fingers longer than those of the first ; in both they cross each other 

 when closed. Following three pairs small, feeble, carrying a strong stiff basecphysis. 



Pleopoda stout, except the terminal pair, which is longer than the telson. 



Habitat.— Station 173, July 24, 1874 ; lat. 19° 9' 35" S., long. 179° 41' 50" R; off 

 Matuku, Fiji Islands; depth, 315 fathoms; bottom, coral mud. One specimen, 

 female. Dredged. 



The appearance of this species is that of an animal that has been subjected to 

 constant lateral pressure, the whole animal being so evenly flattened. The dorsal 

 surface is not carinated, nor compressed to a ridge, but is smooth and rounded; the depth 

 of the carapace increases posteriorly in a line that is continuous with the lower margin 

 of the coxal plates of the pleon until the sixth somite, which is less deep, being 

 much longer than the preceding, and twice the length of the telson. 



The ophthalmopoda are short and stout, and support an ophthalmus that is quite 

 black and somewhat greater in diameter than the stalk, the whole being supported on a 

 pedicle that is abruptly and considerably smaller. 



The first pair of antennae is about half the length of the animal, having the peduncle 

 nearly half the length of the dorsal surface of the carapace ; the first joint is fully equal 

 to the two next, and carries on the outer side a sharply pointed stylocerite of great 

 tenuity, which has the distal extremity twisted to a right angle with the basal portion, 

 and is nearly as long as the joint, the inner side is deep, straight, and flat, being com- 

 pressed against the corresponding margin of the other appendage. The upper and lower 

 surfaces are hollowed, the former to receive the ophthalmopod, and the latter to make 

 way for the second pair of antennae, leaving the inner surface as a wall standing both 

 above and below the extremely thin structure of the joint, and free from hairs or cilia. 

 The two succeeding joints are cylindrical, the second is shorter than the third, and 



