REPORT ON THE AMPHIPODA. 1317 



7. Station 194a; lat. 4° 31' 0" S., long. 129° 57' 20" E.; depth, 360 fathoms. 



8. Station 241 ; lat. 35° 41' N., long. 157° 42' E.; depth, 2300 fathoms (Lanceola 

 pacifica). 



Thus from west to east the genus may be considered as ranging round the 

 world, while from north to south a range is shown of more than ninety degrees, to 

 which may be added about thirty degrees northward, since Lanceola clausii, Bovallius, 

 was taken in "Davis Strait, at lat. 72° N." It is remarkable that each of the 

 Challenger specimens was labelled, not, like most of the Hyperina, with the word 

 " surface," but with the number of fathoms of the particular station, indicating that 

 the specimen was supposed to have come from the great depth mentioned. It may be 

 conjectured that the smallness of the eyes and the soft membranaceous character of the 

 integument are connected with residence in the abysses of the ocean, and the latter 

 character perhaps also with a capacity for passing without injury from the bottom to 

 the surface. The pleopods are well developed, so that the animal may be itself a good 

 swimmer, but, to account for the wide distribution of the genus, it may be supposed 

 that the creature often avails itself of extraneous assistance, the retractile claws of the 

 last three pairs of perasopods being well adapted for giving it a firm hold upon animals 

 of much greater size and speed. 



Family Cysiisomidj, von Willemoes Suhm, 1875. 



The name Cystisomidte was proposed for this famdy by von AVillemoes Suhm in 

 the paper read before the Linnean Society on May 7th, 1874. Under the name 

 Thaumatopsidaa, the famdy was defined by Bovallius in 1886 as follows : — 



" Hyperids with large, tumid head. The eyes large, occupying the upper parts of 

 the head. The first pair of antenna? straight or angularly bent, not tumid. The second 

 pair rudimentary. The mandibles without palp. The seventh pair of pereiopoda 

 [fifth perseopods] not transformed. The inner ramus of the uropoda coalesced with 

 the peduncle ; the peduncles very thick." 



In the Systematical List, 1887, Bovallius gives a similar definition, but omitting 

 all notice of the uropoda, and remarking that the second pair of antennae are rudimentary 

 in both sexes. In the Arctic and Antarctic Hyperids of the same year he gives a 

 third definition, as follows : — 



" Head and body very large and tumid. Eyes large, occupying the upper sides- of 

 the head. First pair of antennae straight, not tumid, few-jointed. Second pair rudi- 

 mentary. Mandibles without palp. Seventh pair of pereiopoda [fifth perseopods] not 

 transformed. Uropoda very thick, prismatic, with distinct rami." 



The description of the uropods as having " distinct rami " is open to misunder- 



