HALIPORUS NEREUS. Igg 



from Pcncopsis, althougli it is said to have but one arthrobranchia on the 

 eighth (second maxillipedal) somite. Xiphopeneus Smith* is distinguished 

 from Pcncopsis by the long stjHibrm posterior legs, the absence of gills on 

 the posterior thoracic somite, etc. 



HALIPORUS Bate. 



Ann. Mag. Nat. Hist., 5tli Ser., VIII. 185, ISSl ; Rep. Challeuger Macrura, p 2S4, 1888. 



Haliporus nereus Fax. 

 Plate XL VIII., Fig. 1-1". 



Bull. Mua. Comp. Zool., XXIV. 213, 1893. 



Integument membranaceous. Carapace lightly granulated. Eostrum 

 about one third the length of the rest of the carapace, horizontal, armed 

 with six teeth above (the hindmost one situated a little back of the orbit), 

 ciliated below. Median dorsal line of carapace carinate, with two teeth on 

 the posterior half of the gastric region. The sides of the carapace are armed 

 with spines as follows : two on the antero-lateral margin, one of which is at 

 the lower angle of the orbit (spina antennalis of Stimp.son), the other over 

 against the second antenna, at the anterior end of the cervical groove (spina 

 branchiostegiana) ; a third spine (spina hepatica) lies on the hepatic region, 

 behind the antennal spine ; a fourth is behind and on the same level with 

 the branchiostegal spine ; a fifth still further back and on nearly the same 

 level, on the hind edge of the cervical groove. The cervical groove is deeply 

 impressed, and the orbital region is definitely bounded by an hepatic and 

 a gastro-hepatic sulcus. The hindmost of the lateral spines of the carapace 

 lies in the anterior angle of a triangular field enclosed by branches of the 

 cervical groove. From the infero-posterior angle of this triangle two carinas 

 run backward along the branchial area ; the upper one ends at the postero- 

 lateral margin of the carapace, the lower one meets the inferior sub-marginal 

 carina of the branchial area before attaining the posterior border of the 

 carapace. These two carime, with the submarginal ridge of the carapace, 

 enclose a long oval area, which forms a conspicuous figure on the branchial 

 regions. The third to the sixth abdominal segments are carinated, their 

 pleur£B broad and roinided. On the sixth segment the carina terminates in 

 a small, acute, horizontal tooth. The sixth segment is twice as long as the 



* Traus. Coim. Arad. of Arts and Sri., II. 27, 1809. 



