242 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 7 



Parapodium with 2 acicula, simple and composite setae, with one or 

 2 presetal and postsetal lobes; branchiae absent or present; 

 aileron generally broadest at the base and terminating distally 

 in one or 2 unequal, slender bars . . . GLYCERA, p. 244 



Genus HEMIPODUS Quatrefages 

 This genus was erected for Hemipodus roseus Quatrefages (1865, 

 pp. 194-196) from Chile. Earlier, Glycera simplex Grube (1856, pp. 

 177-178) had been described from Chile and Peru. This species belongs 

 to the same genus. Schmarda (1861, pp. 93-94) briefly described Glycera 

 dtodon, G. macrorhiza, G. micrognatha, and G. inonodon, all from Chile. 

 Ehlers (1901, p. 155) considered all of the above-named to belong to one 

 species, for which he retained the name, H. simplex (Grube). Arwidsson 

 (1899, pp. 28-30), however, considered H. roseus Quatrefages and H. 

 patagonicus Kinberg (1866, p. 245) distinct from each other. Ehlers 

 based his conclusions on a study of the postsetal parapodial lobes. He in- 

 dicated intergrading variations in these structures, from a simple, round- 

 ed to a bilobed condition, A comparative structure of other parts might 

 have led to different conclusions. A reexamination of either the types or 

 collections from the type localities might prove interesting. 



Later, Hemipodus borealis Johnson (1901, p. 411) was described 

 from the northeast Pacific, and H. californiensis Hartman (1938, p. 93) 

 from central California. These species are separable as indicated in the 

 key below. H. yenourensis Izuka (1912, p. 250) is known only from 

 Japan. 



Several other species, described in the genus Hemipodus, have been 

 transferred to other genera or their affinities are not clearly understood. 

 H. ?nagellanica Mcintosh (1885, p. 349) was later made the type of the 

 genus Glycerella Arwidsson (1899, p. 25). He?nipodus septentrionalis 

 Roule (1896, p. 452) was shown to be a Glycera (Arwidsson, 1899, p. 

 28). Hemipodus mexicanus Chamberlin (1919, p. 349) from the Gulf 

 of California should perhaps be referred to the genus Glycera, since it has 

 both simple and composite setae ; also, the parapodium has 2 long, presetal 

 ligulae, as characteristic of the genus Glycera. Hemipodus canadensis 

 Treadwell (1937, p. 348) from Nova Scotia, Canada, is shown with 

 simple setae (1937, fig. 2) in addition to composite setae, a character 

 which eliminates it from the genus Hemipodus. It is not made known 

 whether the aileron of the proboscidial armature is a bar, such as charac- 

 terizes Hemipodus, or a flaring chitinous piece, as known for Glycera. 

 The parapodia of the latter, however, have 2 acicula, and the composite 

 setae are not so clearly, if at all, heterogomph. 



