MARINE GAMMARIDEAN AMPHIPODA 353 



hrotus, having gone under that name for over 60 years, must now be 

 transferred to Onisimus and the 15 or more species of Onisimus, 

 having gone under that name for nearly 100 years, must now be 

 transferred to a new appellation, which I designate as Boeckosimus 

 in honor of Axel Boeck, one of the first students of Amphipoda to 

 understand the importance of type designations. 



The genus Alibrotus Milne Edwards (1840) ^nth its monotype, A. 

 chauseicus Milne Edwards (1840) may be a senior synonym of either 

 Onisimus (auct. —Pseudalihrotus) or Boeckosimus, new name, but 

 the problem has never been clarified and may be insoluble. The 

 problem should be reviewed at least once more by a student of arctic- 

 boreal faunas and perhaps submitted to ICZN in order to cancel the 

 genus Alibrotus. 



Epistome broadly rounded and projecting slightly in front of upper 

 lip; mandibular molar ridged, palp attached level with molar; gnath- 

 opod 1 subch elate, articles 5 and 6 equal; inner ramus of uropod 2 

 constricted or not; telson short, entire. See Boeckosimus. Species: 7, 

 arctic littoral, Caspian Sea, glacial relicts. 



Opisa Boeck 



Opis Kr0yer, 1842 (homonym, MoUusca). 

 Ovisa Boeck,1876.— Stebbing,1906. 



Type-species: Opis eschrichtii Kr0yer, 1842 (monotypy and sub- 

 sequent synonymy; Boeck (1876) cited 0. typica Kr0yer as type- 

 species, probably as a technical error for he recognized it was a junior 

 synonym of 0. eschrichtii). 



Upper lip rounded, slightly projecting in front of epistome; mandib- 

 ular molar obsolete, palp attached proximally; gnathopod 1 powerful, 

 chelate, chela broad, palm excavate to form thumb; coxa 1 slightly 

 shortened and partially hidden by coxa 2; telson long, deeply cleft. 

 Species: 2, boreal, littoral (to 432 m). 



Orchomene Boeck, new synonymy 



Orchomene Boeck, 1871. — Stebbing, 1906. 



Tryphosa Boeck, 1871.— Stebbing, 1906. 



Orchomenella Sars, 1895.* — Stebbing, 1906. 



Orchomenopsis Sars, 1895. — Stebbing, 1906. 



1 Allogaussia Schellenberg, 1926a. [See also in alphabetical order.] 



Type-species: Anonyx serratus Boeck, 1861 (selected by Boeck, 

 1876). See Sars, 1895* (as Orchomenella ciliata). Regrettably Sars and 

 Stebbing overlooked the fact that Boeck (1876) had selected the type- 

 species of Tryphosa as Anonyx nanus Kr0yer (1846) a species un- 



*This portion of Sars' inonograph was published in 1891. 



