48 THE VOYAGE OF H.M.S. CHALLENGEE. 



shorter than the second ; fourth subequal in length to the second and third taken together. 

 Front tarsus -with, first joint less than one-half (two-fifths) the length of the second. Middle 

 tarsus with first joint seven times longer than the second. 



$ . Length 3, breadth 175, middle femur 3-25, hind femur 2-5 mm. 



? . Length 3, breadth 2, middle femur 3, hind femur 2*25 mm. 



Habitat. — Next to Halohates ivUUerstorffi, the most abundant species, but almost con- 

 fined to the North Pacific Ocean, over which, within or near the tropics, it is widely diffused. 

 Less abundant in the South Pacific. Two specimens, which seem inseparable from sericeus, 

 were taken by the Challenger in the North Atlantic, near the Cape de Verde Islands. 

 Amyot and Serville record its occurrence near the Cape of Good Hope, and Fairmaire 

 from near Madagascar ; but I have not seen specimens from either locality, and it is 

 possible that these were not correctly determined, since any small grey Halohates was 

 always referred to sericeus. 



The specimens I have examined are from the following sources : — 



Challenger Specimens. 



North Pacific localities : — Many stations on the voyage from the Admiralty Islands to 

 Japan, and from Japan to Honolulu (or — in other words — common between the equator 

 and lat. 38° N., and between long. 137^ E. and 154° W., thus ranging considerably north 

 of the tropics). 



South Pacific :— Lat. 23° 4G' S., and long. 149° 59' W. 



North Atlantic :— About lat. 11° N., long. 32° W. 



Specimens from other Soiirces. 



Pacific between Cape Horn and San Francisco {Liverpool Museum). " Ocean Austral " 

 {Berlin Museum). " Pacific— Lat. 24°-34°, long. 120°-115°" {Stockholm Museum). 



$ . Ovate, widest a little before the middle. Ashy grey. Antennge, rostrum, legs, 

 and genital segments fuscous black, clothed more or less with grey pubescence. Head with 

 an ill-defined reddish oblong transverse blotch on each side at the hind margin. Eyes 

 brown or, more rarely, yellowish. Rostrum for apical half, front femora, and last genital 

 segment below more or less shining black. Abdomen with the ventral hind margins some- 

 times very obscurely reddish luteous. 



Antennce (PL I. fig. 7, a.) comparatively stout, about half as long as the body; first 

 joint more than one-third shorter than the other three joints taken together; second 

 incrassate upwards, about two-fifths the length of first; third cylindrical, shorter than 

 the second; fourth stout, slightly and gradually incrassate upwards, subequal in length 

 to the second and tliu'd taken tog-ether. 



