on crustacea brought uv uli willev from tue south seas. 611 



Fam. Nannastacidak. 



1866. Nannastacidae, Spence Bate, Zoological Record (for 186.")), vol. 2, p. 329. 



1878 — 9. Cumellidae, G. 0. Sars, Arrli. Natiirv., vols. S, 4, Middelhavets Cuinaceer, 

 p. 144. 



1880. Cumellidae, Kossmanii, Zoo). Ergebu. Rcise Rothen Meere.s, Malaco.straca, 

 p. 90. 



1887. Cumellidae, Sai"s, Challciigcr llfport.«, vol. 19, Cumacea, p. 62. 



18!);>. Nannastacidae, Stebbiiig, History of Crustacea, Iiiteniat. Sci. Ser., vol. 74, 

 p. 30.-). 



189.5. Natinastacidae, Hansen, Isop. Cuiiiac. Stoinat. Plankt(»n-Exp., p. 09. 



1900. Nannastacidae, G. O. Sars, Crustacea of Norway, vol. 3, p. 79. 



This family agrees with the Canipyla.s)»idae in sevi'ral respects, having no distinct 

 telson, no pleopods iii the male, inner branch of the uropods one-jointed, the firat and 

 second peraeopods in the female, but the third and fourth also in the male, furnished 

 with exopods. In the mouth-organs there are very considerable differences, the man- 

 dibular molar being blunt in the present family, but acute in the Campylaspidae, 

 while also in that family the second ma.xillae are formed of a simple plate, but have 

 the usual subdivisions in the Nannastacidae. In 1896, however. M. Jules Bonnier 

 described two species of a new genus Procanipylaspis, in which the molar of the 

 mandible is acute, but the second inaxillac arc iiorniai. Sars in IDOO inclines t(j the 

 view that Procampylaspis ajiprouchcs nearer to the Nannastacidae than to the other 

 family. The three pairs of maxillipeds have peculiarities which may relieve the 

 difficulty by removing Procampylaspis from both the contending families. 



Gen. Nannastacus. 



1865. Nannastacus. Bate, Ann. Nat. Hist., Ser. 3, vol. 15, p. 86. 



1875. Diops, Paulson, Crustacea of the Red Sea (in Ru.ssian), p. 128. 



1878 — 9. Nannastacus, Sars, Middelhavets Cumaceer, p. 160. 



1880. Nannastacus, Ko.ssmann, Zool. Ergebn. Rothen Meeres, p. 90. 



1887. Nannastacus, Sars, Challenger Reports, vol. 19, Cumacea. ]). ()2. 



1893. Nannastacus, Stebbiiig, History of C'rnstacea, p. 305. 



1895. Nannastncus, Hansen, Isop. Cumac. Stoinat. Plankton-E.\p., p. 59. 



This genus i.s distinguished from all other ( 'uniacean geiu'ia at present known by 

 having two distinct eye.s. At various dates it has had a.ssigned to it the species 

 uni/uiculatus Bate, longirostris Sal's, Sarsii Ko.ssmann, Sulimli Sai-s, liirsutus Han.son, 

 and the Diops spinosus and Diops parvulus of Paulson. Ko.ssmann considere it possible 

 that his own species may be a synonym of Paulson's parvulus. Both sexes have been 

 described onlj- in the ca.se of unguiculatus, lonffiro.stris, and Sulimii. In reganl to the 

 fii-st two the .sexual dimorphism so common in the present order is le.ss striking than 

 usual, but in the third it is strongly accentuated. Hence the (|uestion arises whether 

 the form described by Sars as the male of his ,V. Suliniii m,iy not really represent 



w. V. 81 



