270 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 15 



Haploscoloplos cylindrifer (Ehlers) 1905 



Scoloplos cylindrifer Ehlers, 1905, pp. 45-46, pi. 6, figs. 16-19; Augener, 

 1914, pp. 29-30, pi. 1, fig. 4; Augener, 1926, p. 166; Augener, 

 1927b, p. 353. 

 Haploscoloplos cylindrifer Monro, 1939b, pp. 124-125, figs. 13 a-c. 



According to the several accounts indicated above, based on indi- 

 viduals originating from New Zealand (Ehlers, 1905), Australia 

 (Augener, 1914) and Tasmania (Monro, 1939b), it is generally agreed 

 that the prostomium is conical in mature specimens and that thoracic 

 parapodia have only pointed setae. In some posterior abdominal segments 

 the branchiae are divided in dichotomous arrangement (shown by 

 Augener, 1914, pi. 1, fig. 4, and by Monro, 1939b, fig. 13). 



According to Ehlers (1905) the body is about 17 mm long, 1.5 mm 

 wide, and consists of about 115 segments; branchiae are present from 

 setigerous segment 18 or 25 and cylindrical in shape; the prostomium 

 is acutely triangular and longer than wide; the peristomium is a smooth 

 ring. In posterior neuropodia there are a few setae and sometimes pro- 

 jecting acicula. This recalls the diagnostic feature in Scoloplos (Leo- 

 damas) (see below). Abdominal neuropodia have a long vertical flange 

 continuous with the parapodial ridge and extending beyond the sub- 

 podial thickening (shown by Ehlers, 1905, pi. 6, fig. 19). 



Augener (1914, pp. 29-30) described the prostomium as oculate; 

 branchiae are present from setigerous segment 17 or not before 22 and 

 bifid from about branchial segment 37, with the number of terminal 

 filaments increasing to 4 in posterior segments. Augener (1926, p. 166), 

 in collections from Dunedin, New Zealand, noted that branchiae are 

 distally bifid or trifid, and (1927b, p. 353), in individuals from Tau- 

 ranga, New Zealand, noted an anterior abranchiate region of 19 to 21 

 segments and divided branchiae farther back. 



Monro (1939b, pp. 124-125), in specimens from Tasmania, found 

 branchiae first present on segments 24 to 29 or not before 50; they 

 were simple for about 25 segments and dichotomously branched there- 

 after, with up to 5 terminations (Monro, fig. 13) ; transition from 

 thorax to abdomen was at about setigerous segment 14. 



If these accounts refer to a single species, the degree of variability is 

 considerable, with branchiae not present before segment 17 to 50. 

 Thoracic parapodia have conspicuous rounded, lamellar postsetal lobes 

 in anterior segments. These lobes increase in length and are distally 



