CALIFORNIA STALK-EYED CRUSTACEA. 33 



Genus Hyastenus White. 



Carapace subpyriform, convex, smooth, tuberculated, or spiny. Spines 

 of rostrum long, slender, and diverging from the base. Preocular spine 

 small or obsolete. Eyes small, the peduncles slender and completely 

 retractile within the small orbits which have a lateral aspect, and a fissure, 

 or hiatus in the upper«and lower margins. Basal antennal joint large; 

 flagellum usually exposed and visible from above at the sides of the ros- 

 trum. Ambulatory legs elongated, subcylindrical and unarmed, the first 

 pair usually much the longest. Abdomen of the male seven-jointed. 



This genus is divided by Miers into two subgenera, 

 which, however, ''are connected together by numerous 

 gradations." The one, Hyastenus, is characterized by 

 having few or no spines on the carapace and by the 

 absence of a spine at the external angle of the basal 

 antennal joint. The other, Chorilia, has the carapace 

 spiny and the basal antennal joint is furnished with a 

 spine. Hyastenus (Chorilia) longipes is the type of the 

 latter subgenus. 



Hyastenus (Chorilia) longipes (Dana). 



Chorilia longipes Dana, Am. Journ. Sci. (2), Vol. XI, 1851, p. 269; Crust. 



U. S. Expl. Expd., Part I, 1852, p. 91, PI. I, fig. 5. Stimpson, Journ. 



Bost. Soc. Nat. Hist., Vol. VI, 1857, p. 455. Lockington, Proc. Cal. 



Acad. Sci., Vol. VII, 1877, p. 69. Whiteaves, Can. Nat. (2), Vol. 



VIII, 1878, p. 470. Kathbun M., Proc. U. S. Nat. Mus., Vol. XXI, 



1898, p. 572. 

 Hyastenus {Chorilia) longipes Miebs, Journ. Linn. Soc. London, Vol. XIV, 



p. 658; Proc. Zool. Soc. London, 1879, p. 27. 

 Hyastenus japonicus Miers, Proc. Zool. Soc. London, 1879, p. 27, PI. I, 



fig. 2; Challenger Reports, Vol. XVII, 1886, p. 56, (fide Rathbun M.). 

 Hyastenus longipes Miers, Challenger Reports, Vol. XVII, p. 56. Rathbun 



M., Proc. U. S. Nat. Mus., Vol. XVI, 1893, p. 85, PL VII. Newcombe, 



Bull. Nat. Hist. Soc. Brit. Col., 1893, p. 20. 



Carapace pyriform, inflated, and covered with sharp spines of unequal 

 size. Median region tumid, with two median spines and a row of three 

 spines on either side, the posterior one being the largest and situated a 

 little behind the middle of the interval between the two spines on the 

 middle line; a prominent spine on the tumid hepatic region; several small 

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