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



on the ventral surface of the two hindermost legs. They are here placed at the tip of a 

 small tubercle, which is likewise absent on the two first pairs of legs. The genital pores 

 of the males are almost quite covered by the surrounding hairs. 



This hairy Pycnogonid was dredged by the Challenger at two different stations. 



Station 147. December 30, 1873. Lat. 46° 16' S., long. 48° 27' E. Depth of the 

 sea, 1600 fathoms. Temperature of the bottom, 0'8° C. Bottom of the sea, globigerina 

 ooze. 



Station 157. March 3, 1874. Lat. 53° 55' S., long. 108° 35' E. Depth of the sea, 

 1950 fathoms. Bottom of the sea, diatom ooze. 



Observations. — The near relation which this beautiful deep-sea species bears to the 

 two foregoing ones is evident. They form the true deep-sea representatives of the genus 

 Phoxichilidium, Milne- Edwards, which probably will be found to have an extremely 

 wide range. 



Hannonia, n. gen. 



Diagnosis. — Proboscis stout, inserted quite in front of the cephalothoracic segment. 

 Mandibles rudimentary, small, two-jointed, chelate. Palpi wanting. Ovigerous legs, 

 present in both sexes, ten-jointed. 



Hannonia typica, n. sp. (PL XIV. fig. 8-11). 



Diagnosis. — Body robust, proboscis long-ovate, truncated at the tip, and forming a 

 narrow stalk posteriorly. Legs short, with a small first tarsal joint and a claw, without 

 auxiliary claws. 



Description. — 



Length of the proboscis, ....... 4 mm. 



Length of the trunk with the abdomen, . . . . . 7 „ 



Total length of the body, . . . . . . . 11 ,, 



Length of the leg of the third pair, . . . . . . 12 „ 



This curious sea-spider has a robust body ; the cephalothoracic segment is not very 

 large, and, like the two following segments, its hinder margin is furnished with an 

 elevated ridge ; on these ridges a row of small hairs is inserted. The oculiferous 

 tubercle is blunt, and placed in the middle of the cephalothoracic segment. It is 

 furnished with four comparatively large black-coloured eyes. The dorsal surface of the 

 lateral processes, like that of the last thoracic segment immediately in front of the inser- 

 tion of the abdomen, shows rounded protuberances, on the surface of which small hairs — 

 like those of the ridges on the hinder side of the thoracic segments — are placed. 

 The abdomen is not very long, but stout and swollen at its extremity. Its surface is 

 likewise covered with numerous small hairs. The form of the proboscis is ovate ; at the 

 anterior end it is flattened and truncated. The mouth is found in the middle of this trun- 

 cated surface ; it is triangular, with comparatively large lips. At the back the proboscis is 



