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



lateral margin of the carapace has three prominent spines on its middle third, and a few 

 spines of smaller size are situated between the first of these and the antero-lateral angle. 

 A few minute spinules occur on the anterior part of the pterygostomial region. 



The chelipedes and ambulatory limbs are wanting in the single specimen. 



The eyes are of small size, and somewhat wider at the base than at the free end ; the 

 cornese are minute but deeply pigmented. The antennal acicle is broad and acuminate, 

 slightly exceeding the peduncle in length ; the terminal joint of the peduncle is pro- 

 longed on one side into a delicate spine ; the flagellum is absent on both sides of the body. 

 The carpal joint of the external maxillipedes is of smaller size than usual, and the outer 

 and distal end of the merus is prolonged into a minute denticle. 



The abdominal segments are smooth and glabrous externally, while their pleura are 

 subacute. 



Although the collection contains but a single specimen, and that in a very imperfect 

 state of preservation, the characters are in some respects so striking that I have felt 

 justified in making it the type of a new species. It may be distinguished at once from 

 all the other known species of Uroptychus by the form of its rostrum. 



Breadth of carapace 4-3 mm., length of body (including rostrum) 12 mm., of carapace 

 5 "5 mm., diameter of ova about 0"6 mm. 



Habitat. — Amboiua. The label gives the depth as 15 fathoms, but from what is 

 known of the bathymetrical distribution of the genus it is probable that the specimen 

 came from one of the deeper dredgings in that locality. 



