AMPHIPODA OF THE SCOTTISH NATIONAL ANTARCTIC EXPEDITION. 191 



The small amount of difference between some of these genera, and the difficulty of 

 referring a species to its proper genus, is shown by the fact that while CHEVREUX estab- 

 lished for the species in question the new genus Waldeckia, and compared it with 

 Menigraies and Lepidepecreum, Mr WALKER, who was independently working at the 

 same species, had at first classified it under Socarnes, and Mr STEBBING has since stated 

 that he would have been inclined to concur in this view. Mr STEBBING has, however, 

 now accepted the genus Waldeckia, and has described a new species, W. chevreuxi, from 

 Australia (1910A, p. 572, pi. xlvii.B). This species, which, though undescribed, has 

 been long known to me from New Zealand, differs from W. zschauii (Pfeffer) in having 

 the first gnathopod quite simple, and thus offers an additional reason for retaining the 

 genus Waldeckia, unless indeed W. chevreuxi could not have been as appropriately 

 placed under one of the existing genera. 



Genus ORCHOMENOPSIS Sars, 1893. 



Orchomenopsis nodimanus Walker. 



Orchomenopsis nodimanus Walker, 1903A, p. 44, pi. vii. figs. 13-17. 

 Stebbing, 1906, p. 721. 



South Orkneys, Scotia Bay, Station 325 ; trap. Many specimens, averaging 



about 15 mm. 

 South Orkneys, Scotia Bay; 10 fathoms. March 1903. Three specimens, the 



largest 13 mm. 



South Orkneys, Scotia Bay ; 9-10 fathoms. April 1903. One specimen. 

 Also taken at other times along with 0. chilensis (Heller). 



These specimens agree well with the description given by WALKER, and I have 

 been able to compare them with co-types of his species from the British Museum, 

 and find no essential difference between the specimens from the South Orkneys and 

 those from South Victoria Land. The species in most respects is very similar to 

 0. chilensis (Heller), but can be distinguished by the slight carination of the hinder 

 part of the body and by the peculiar structure of the propod of the first gnathopod ; 

 in most of my specimens this is a little stouter than is shown in WALKER'S figure, 

 and it bears a tubercle on the posterior surface as described by him. 



This species occurred along with 0. chilensis (Heller) in many captures. 



Orchomenopsis chilensis (Heller). 



Anonyx chilensis Heller, 1865, p. 129, pi. xi. fig. 5. 



Orchomenopsis obtusa Sars, 1891 and 1895, p. 74, pi. xxvi. fig. 2, and p. 684. 



Orchomene musculosus Stebbing, 1888, p. 673, pi. xx. 

 (?) abyssorum Stebbing, 1888, p. 676, pi. xxi. 

 (?) cavimanus Stebbing, 1888, p. 679, pi. xxii. 



Orchomenopsis musculosa and (?) abyssorum Stebbing, 1906, p. 84. 

 (1) zschauii Stebbing (part), 1906, p. 85. 



(ROT. BOG. KDIN. TRANS., VOL. XLVIII., 473.) 



