286 THE VOYAGE OF H.M.S. CHALLENGER. 



unites Gammarus Jn'^yeri, Rathke, to Gammarus pmcihtrus of the same author, both of 

 which are synonyms of Gammarus marinus, iu Boeck's view. Under the Gammaropsis 

 division he describes Gammanis erytkrophthahnus, u. s., which Boeck accepts as type of 

 the genus Gammaropsis. Spence Bate and Bruzelius did not take account of the name 

 Gammaropsis, as in Liljehorg it was only provisional, but to Ewystheus erytlirophthahnus, 

 Spence Bate, Boeck gives the name Gammaropsis erythrophthalmiis. G. O. Sars, however, 

 maintains that the species which Boeck describes under this name is not Liljehorg's species, 

 " which, among other things, has the secondary flagellum on the upper antennse consider- 

 ably longer and consisting of numerous articulations, the lateral angles of the head 

 rounded off, and the third pleon-segment's lower hinder angles not acute. Lastly, in 

 Boeck's species, the pigment of the eyes is not red as in the typical form but black." A 

 point which Sars does not mention is that in Boeck's species the fourth pleon-segment has, 

 on the middle of the hinder rim, two small teeth, whereas Liljehorg expressly says 

 "annuli abdominis supra sine aculeis." On the other hand, Boeck says nothing of the 

 colour of the eyes, and Lnjeborg says nothing as to the other points mentioned by Sars, 

 except that the accessory flagellum is long, six-jointed. As Boeck does not appear to have 

 himself taken the species which he describes, he probably had no means of ascertaining 

 the colour of the eyes, but it still remains rather remarkable that both in his species and 

 in LUjeborg's, the hands of the second gnathopods should be tridentate in the male and 

 bidentate in the female. To Boeck's species Sars gives the name Gammaropsis melanops. 

 Eor the opinion that Gammarus (Gammaropsis) erytlirophihalmus, LUjeborg, had been 

 earlier described as Gammarus niaculaiiis, see Note on Johnston, 1827-1828. The other 

 species here described as new, Gammarus (Gammaropsis) macronyx, is assigned by Boeck 

 to Protomedeia fasciata, Kr0yer. 

 The subdivision or subgenus Gammaropsis is thus defined : — 

 "t Rami pedum spuriorum ultimorum depressi, lamellosi Gammarus." 



" tt Rami pedum spuriorum ultimorum stiliformes, conici. Appendix caudalis unica, tuberculi- 

 formis, Gammaropsis." a) Pedes thor. 3:tu et 4:ti paris solito modo formati. Gammarus 

 erythrophthalmus, n. s. h) Pedes thor. 3:tii et 4:ti paris forma singulari, ungue 

 longissimo, parum arcuato, articulo 5:to et 6:to una formato. Gammarus anomalus, 

 H. Rathke ; Gammarus longipes, Liljehorg ; Gammarus macronyx, n. s. 



1855. LiNDSTROM, G., boru 1829 (G. 0. Sars). 



Bicbag till kannedomen om Ostersjons invertebrat-fauna. Ofversigt af Kongl. 

 Vetenskaps-Akademiens Forhaudlingar. Arg. 12. 1855. No. 2. Stockholm, 

 1856. pp. 49-73. 



Lindstrom here describes the new genus Bathyporeia as follows : — " Antennse superiores articulo 

 primo peduncuH magno et tumido, flagello appendiculari perpusillo. Antenna inferiores 

 pedimculo gracili, fere duplo longiore pedunculo superiorum. Mandibute apice valde 

 acuminate, palpo triarticulato, articulo secundo crasso. Palpus pedum maxiUarium 

 articulatus, articulo secundo lato et foliaceo, articulo tertio gracili, curvo et non ut 

 plerumque ad ajjicem articuh prsecedentis, sed, palp)i quasi appendicularis modo, ad 

 marginem extcriorem afiixo. Pedes thoracici primi jsaris perbreves, debiles, articulo 

 ultimo pyiiformi, ungue valido. Pedes secundi paris prsecedentibus duplo longiores, 

 ungue carentes. Pedes tertii quartique paris inter se similes, ultimo articulo longo, gracili, 

 curvo, ungue rudimentario. Quinti paris pedes femore magno, clypeiformi, articulo tertio 

 lamelloso, articulo quinto sine ungue. Epimera parva, margine inferiore setis instructo. 

 Pedes natatorii forma vulgari. Pedes spurii quarti quintique paris breves. Pedes spurii 



