134 STALK-EYED CRUSTACEA. 



pair of legs. A flat, rather stiff, rouiuled plate projects outward from the 

 second segment of the third maxilliped, as in S.ferox, agassLdi, and pivcax. A 

 similar but narrower process is found on the proximal segment of the second 

 pair of legs, closely applied to the outer and hinder part of the basal segment 

 of the first pair of legs. This process is also found in S.ferox, although it is 

 not mentioned nor figured by G. 0. Sars. It is present, too, in S. ugasHzii 

 and *S'. procax. 



Of the five hitherto known species of Sclcrocmngon, viz. bonus (Fab.), sale- 

 f)rosa {Owen), aiigiisiicaitda (De E.iVdn),fcroj.- {G. 0. Siwi^),* Jacqitefi {A.M. Edw.),t 

 and agassim Smith, S. fero.v bears the closest resemblance to the present 

 species. The peculiarities of the genus Sclcrocrangon are so fully described 

 and figured by Sars in his account of S. ferox (Norske Nordhavs-Exped., 

 Crustacea, I. 15-26, Plate II., 1885), that it would be superiluous to give a 

 detailed de.scription of S. airox. Let it suffice to point out the specific dif- 

 ferences between these two species : in 8. ferox the upturned rostrum is 

 simple, while in S. atrox a long acute tooth, given off from its ventral side, 

 reaches as far forward as the tip of the rostrum ; in other words the ros- 

 trum is bifid in the vertical plane. In the former species the dorsal carinas 

 of the sixth abdominal segment bear two pairs of well developed spines, 

 while in the latter wo find but one pair of very small spines at the posterior 

 end of the carinse. The pleural spines of the abdomen are much longer in 

 the former species than in tlie latter, and on the fifth somite there are four 

 to five spines on each pleura, against two in S. alrox. The eyes are nnich 

 smaller in S. ferox, and are destitute of the S2)ine above the cornea which 

 is seen in S. atrox. Finally, in Sars's species the antennal scale is much 



• Cheraphilm ferox G. O. Sars, Ai-cli. for Mathematik ojj Naturvidcuskab, II. 339, 1877 ; Silcrurrmit/on 

 salehrosus G. 0. Sars, Ucn Norske Nordliavs-Exped., Crustacea, I. 15, 1885 (iwc Owen) ; Sclerocraiiyon 

 ferox Hansen, Dijniplma-Togtets Zoolog.-Bot. Ldbytte, p. 230, 1887. G. 0. Sars says that the Mediter- 

 ranean species. Cancer cataphraclus Olivi (^Eyeon toricatns Risso), perliaps belongs to the genus Sclcrocran- 

 gon. If tills were so, the name Sclcrocrangon would have to give way to Egcon Risso. But examination 

 of Olivi's species shows Ihat Sars's surmise is incorrect. The rostrum in this species is short and bifid, the 

 antennal scale short and broad, the inner branch of the abdominal appendages is large (subequal to the outer 

 branch), and furnished with a stylaniblys on every pair; there are six well developed gills on each side of the 

 body, a small podobranchia at tiic base of the second maxilliped, and the basal segment of the first pair of legs 

 bears a uniarticulate cxopod. Risso's genus Egeon {/Egteoif] (Hist. Nat. dcs Crustaces des Environs de Nice, 

 p. 99, 181G), established to receive this species, is based on valid structural characters and should be restored 

 («. Ortinann, Zoolog. Jahrb., Abth. f. Syst., V. 530, 535, 1890). Spencc Bate's Ponlocaris (Rep. Chal- 

 lenger Macrura, p. 495), appears to be the same as Egeon. Miers (,\nn. Mag. Nat. Ilist. 5tli Scries, VIII. 

 .J05, 1881) assigns Cancer cataphractm Olivi to the gen\is Cheraphilus, althougli this species was made the 

 type of the genus Egeon by Risso forty-six years before the name Cheraphilus was proposed by Kinalian ! 



t Pontophiluf jucqueti A. M. Edw., Comptes Rcndus, XCIII. 935, 1881 ; Recueil de Figures dc Crus- 

 laccs nouv. ou pen connus, 1883. Closelv allied to, if not (he same as, S. agassizii Smith (Bull. Mus. Comp 

 Z'.ol., X. 32, 18S2) 



