654 



THE VOYAGE OF H.M.S. CHALLENGER. 



produced in the median line ; the two following somites are short ; the sixth is about once 

 and a half the length of the fifth. 



Telson long, slender, slightly depressed in the dorsal median line, and furnished with 

 three small spines on each side on the dorso-lateral surface. Appendages rather long, 

 slender, armed with small, feeble teeth. 



Habitat— Station 192, September 26, 1874; lat. 5° 49' 15" S., long. 132° 14' 15" 

 E.; off the Ki Islands, south of New Guinea; depth, 140 fathoms; bottom, blue mud. 

 One specimen. Trawled. 



The carapace is smooth and polished, laterally compressed and elevated to a carina 

 over the gastric region, where the crest is armed anteriorly with two large fixed teeth, 

 and posteriorly with five movable spines furnished between with fine hairs (fig. 1, r.c). 

 The rostrum is as long as the carapace, curved obliquely upwards in a crescentic form, it 

 is smooth on the upper surface, except for the presence of two small teeth near the apex, 

 and armed on the lower margin, from base to apex, with fifteen evenly disposed teeth. 

 The frontal margin of the carapace is armed with a small antennal and a smaller fronto- 

 lateral tooth. 



The pleon is smooth, having the third somite arcuate, slightly compressed dorsally and 

 posteriorly produced, but not carinated ; the sixth somite is very short. 



The telson (fig. lz) is laterally compressed, shorter than the outer ramus of the 

 rhipidura, and dorso-laterally armed on each side with three small solitary spines. 



The ophthalmopoda (fig. la) are longitudinally pear-shaped ; each stands on a small 

 pedicle at the extremities of the ophthalmic somite, near the outer angle of the orbit, and 

 directed obliquely outwards and forwards. The ophthalmus is hemispherical, the circum- 

 ference being indented by a crescentic extension of the margins, which is produced by 

 the presence of a large ocellus or secondary eye. This is circular in form and projects 

 beyond the surrounding surface. Although close to the margin of the true eye it is 

 distinctly separated from it, and divided into larger facets than those that exist on the 

 principal organ. 



The first pair of antennae (fig. lb) carries a long, sharp stylocerite that reaches as far 

 as the distal extremity of the third joint of the peduncle. The flagella are slender and 

 as long as the rostrum. 



