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



sea, 1600 fathoms. Temperature of tlie bottom, 0"8° C. Sea bottom, globigerina 

 ooze. 



Station 300. December 17, 1875. Lat. 33° 42' S., long. 78° 13' W. Deptli 1375 

 fathoms. Bottom temperature, 1"5° C. Sea bottom, globigerina ooze. 



Of all the species of this genus known at present, this species of Colossendeis shows 

 Ijy far the greatest affinity with Colossendeis leptorhynchus, which I shall describe further 

 on. The latter species, however, is much more slender, 



Colossendeis leptorhynchus, n. sp. (PL VIII. figs. 3-7). 



Diagnosis. — Proboscis almost cylindrical. Cephalic part of the cephalothoracic seg- 

 ment distinctly separated from the thoracic part ; eyes obsolete ; third joint of the palpus 

 shorter than the fifth ; palpus much longer than the body. Legs and proboscis 

 extremely slender. Claws of the legs minute. 



Description. — 



Length, of tlie proboscis, . 



Length of the trunk with the abdomen. 



Length of the abdomen, . 



Length of the palpus. 



Length of the ovigerous legs. 



Length of the leg of the third pair. 



The body, and especially the proboscis and legs, are a great deal more slender than 

 in Colosse7ideis gigas. The intervals between the lateral processes are not quite so wide 

 as the thickness of these processes. The surface of the body is quite smooth, but the 

 palpi and ovigerous legs, and the last five joints of the legs, are furnished with extremely 

 small hairs. 



The proboscis is extremely long, more than twice as long as the trunk ; about the 

 middle it is slightly swollen. The cephalic part of the cephalothorax is distinctly 

 separated from the thoracic part. It is elongated, a little more slender towards the end, 

 and bears on the dorsal surface, about the middle, a small blunt knob as a rudimentary 

 oculiferous tubercle. 



The four thoracic segments are closely united. The abdomen is small, about 1-1 8th 

 of the total length of the body. The palpi are not very long. The first two and the 

 fourth joints are extremely small ; the third is long, and the fifth a great deal longer stiU, 

 The sixth joint is shorter than the seventh, and of the last three joints (fig. 5), the third 

 is by far the longest. The relative lengths of the joints of the ovigerous legs is the 

 same as in Colossendeis gigas, Hoek ; the sixth joint is again considerably longer than 

 the fourth, and the fifth is extremely short. The last four joints decrease in length, and 

 the claw is very smaU (fig. 6). 



The first three joints of the legs are very small, nearly as long as broad ; the following 



