186 THE VOYAGE OF H.M.S. CHALLENGEE. 



4. ai^pendieulata, answering to " Lysianassa appendimlata vel Anonyx appendiculatus, 

 Kroyer ; " 5. atlcmtica, for his own Gammarus atlanticus ; with the concluding 

 observation that Cancer ampulla, Phipps, and the imperfectly known Cancer nugax, 

 Phipps, appear also to belong to this genus. 

 He forms the new genus Alihrotus with the one species " Cliauseicus," to receive Lysianassa 

 chauseica, Milne-Edwards, and defines it thus : — " Les Alibrotes, que nous avions d'abord 

 r^unies aux Lysianasses, s'en distinguent par la longueur considerable des antennes et la 

 forme grele de celles de la premiere paire, qui ressemblent tout-a-fait k celles des Crevettes, et 

 par la conformation des pates des deux premieres paires qui sont grandes, fortes et propres a la 

 marche et k fouir ; elles ont h peu pris la meme forme et se terminent par un grand article 

 plat et allonge, dont le sommet est armd d'un ongle gros, conique, et k peine flexible. Du 

 reste, ces animaux ne different pas notablement des Crevettes." To this genus Spence Bate 

 in the Brit. Mus. Catal., p. 86, adds " Anonyx littoralis, Kroyer, Voy. en Scand. pi. 13. f. 1.," 

 but without reference to Kr0yer's own account of it, Nat. Tidssk. 2. K. 1. B. 1844, pp. 

 621-629, which describes the first joint of the upper antennaj as of the thickness usual 

 in the genus Anonyx, and the second gnathopod as nearly filiform. Boeck includes 

 Anonyx litoralis, Kr0yer, and two other species in a new genus Onesimus, to which he 

 appends Alihrotus as a doubtful synonym. 

 Milne-Edwards next gives Pldias, Guerin, with its one species, serratus, Gu^rin. Acanthonotus, 

 "Owen et J. C. Eoss," receives the species (1) cristatus, Owen; (2) Nordmannii, n. s., 

 thus described : — " Front depourvu de rostre, mais formant au-dessus de la base des 

 antennes inferieures, une grande protuberance qui loge les yeux, et qui porte a son extremite 

 les antennes superieures (h. peu pies comme chez les Ischyrocferes). Antennes tres-greles et 

 assez longues ; le pMoncule de celles de la paire [supt^rieure] trfes-court, et le filet terminal 

 long, mais ne depassant que de peu le pedoncule des antennes infiJ^rieures. Thorax et 

 abdomen arrondis et sans dents ni epines en dessous. Pieces epimeriennes des quatre 

 premiers anneaux extremement grandes. Pates de la premiere paire ayant leur p^nulti^^me 

 article elargi en dessous, jjres de sa base, et la griffe assez longue, de fagon a ressembler k 

 une petite main tres-imparfaite. Pates de la seconde paire filiformes et sans trace 

 d'une main prehensile. Pates de la troisi^me et de la quatrifeme paire ayant leur 

 troisifeme article tres-grand, et elargi, les deux suivants ti-fes-petits et le dernier trfes- 

 long, mais grele et styliforme. Pates des trois derniires paires courtes, mais ayant leur 

 premier article tres-grand et presque aussi large que long. Fausses pates de la 

 dernifere paire beaucoup plus saillantes que celles des deux paires prec^dentes, et pourvnes 

 de deux lames lanceolees de meme longueur. Abdomen termini par deux lames sublanceol^es 

 dont le bord interne est droit. Longueur environ 5 lignes. Habite les cotes de la 

 Crimee." This species appears to bo stLU. unidentified. It does not appear among the 

 Mediterranean species in the recent work by Victor Carus. In the Brit. Mus. Catal., 

 Spence Bate re-names it Protomedeia nordmannii. Kr0yer, Nat. Tidssk., 4 Bd. 1842, 

 p. 161. n., had already expressed his belief that the species could not be retained in the genus 

 Acanthonotus, but without proposing to place it in the genus Protomedeia, which he had 

 just instituted, loe. cit., p. 154, and since to that genus he assigns "Epimera sat brevia," 

 ^ while to AcantJionofus worf??Haw?«» Milne-Edwards assigns "Pieces epimeriennes des quatre 



premiers anneaux extremement grandes," the union of this species to that genus is hardly 

 likely to stand. The difficulty of such union is augmented by the statement in Boeck, De 

 Skand. og Arkt. Amph. p. 576, that "Pedes secundi paris piarvi, manu non instructi 

 subcheliformi " in Kr0yer's generic definition is a slip of the pen for "Pedes primi paris." 

 Milne-Edwards considers rightly that Amphitoe seira, Kr0yer, ought to be placed in the 

 genus Acanthonottis, and wrongly that 0?iiscus cicada of Otho Fabricius is probably the 

 same species ; he thinks further that Gammarus spinosus, Montagu, the type of Leach's 



