856 



THE VOYAGE OF H.M.S. CHALLENGER. 



spines, commencing over the gastric region and on the lower margin with seven or 

 ei^ht long ones. Antennal teeth on the frontal margin small. 



Pleon dorsally smooth ; third somite considerably longer than the others, and dorsally 

 arcuate, slightly confessed, and posteriorly projecting in the median line ; sixth somite 

 slightly longer than the fifth. 



Telson as long as the two preceding somites, dorsally flattened, and having the dorso- 

 lateral angles armed with several small spinules arranged in a longitudinal row. 



Ophthalmopoda pyriform. 



First pair of antennae having the flagella short, scarcely reaching beyond the 

 rostrum. 



Second pair of antennae having the scaphocerite long and slender, two-thirds the 

 length of the rostrum. 



Pereiopoda smooth and generally free from spines on the anterior margin, and 

 posteriorly fringed with long hairs. 



Length, entire, 



,, of carapace, 



,, of rostrum, 



„ of pleon, . 



,, of third somite of pleon, 



,, of sixth somite of pleon, 



„ of telson, . 



26 mm. (1 in.). 



8 



9 

 18 



5 



3 



5 



Habitat. — Station 219, March 10, 1875 ; 

 the Admiralty Islands ; depth, 150 fathoms ; bottom, coral mud. 

 laden with ova. Trawled. 



at. 1° 54' 0" S., long. 146° 39' 40" E.; off 

 One specimen, female, 



The specimen from which this description is taken is a distinct and fixed species, 

 and may readily be distinguished from the others by the greater length and by the form 

 of the third somite of the pleon, and by the general armature being less pronounced. 

 In the other species the spines on the upper margin of the rostrum are larger than those 

 on the lower, but in this species they are finer and less conspicuous, and more regularly 

 placed than those on the lower, and the antennal teeth on the frontal margin are not so 

 well developed. 



The ophthalmopoda are less stout and carry a black ophthalmus that is furnished 

 with a small circular ocellus. 



The first pair of antennas does not reach beyond the extremity of the rostrum, the 

 outer flagellum being thick nearly to the apex, where it is suddenly reduced to a thread- 

 like extremity of a diameter simdar to that of the inner flagellum ; the first joint is long 

 and depressed on the upper surface, and carries a sharply pointed stylocerite that is about 

 half the length of the joint. 



