NO. 3 HARTMAN : ORBINIIDAE, APISTOBRANCHIDAE, PARAONIDAE 289 



Abdominal notopodia have a long triangular postsetal lobe and 10 

 to 12 longer to shorter pointed setae accompanied by two furcate setae. 

 Abdominal neuropodia have a postsetal lobe that is much shorter and 

 triangular. The single projecting aciculum at maximum development has 

 a characteristic shape, not found in the type from southern South Amer- 

 ica; in its distal end it is sharply recurved in the form of an inverted 

 capital J; its basal shaft is dark to light brown, its distal end is paler. 

 The aciculum is accompanied by about six slender pointed setae. 



The pygidium is surrounded by a thick flange and two pairs of 

 tapering cirriform appendages; a longer pair is inserted at the sides and 

 a shorter pair ventrally; the largest are slightly longer than the depth 

 of the anal ring and the others are about two-thirds as long. 



The individuals from Lower California were first thought to differ 

 from S. (L.) ohlini from Tribune Bank, South America, especially be- 

 cause of the sharply recurved acicula in abdominal neuropodia. It was 

 found however that these characteristic recurved acicula are absent from 

 anterior abdominal neuropodia. In other respects, especially in the great- 

 ly depressed thorax, the unadorned thoracic neuropodia, and the cus- 

 pidate thoracic uncini, there is close agreement. 



Distribution. — S. (L.) ohlini is recorded from southern South 

 America (Ehlers, 1901) and off Lower California, Mexico. 



Scoloplos (Leodamas) marginatus (Ehlers) 1897 



Aricia marginata Ehlers, 1897, pp. 95-97, pi. 6, figs. 150-156; Ehlers, 



1908, pp. 116-117; Monro, 1930, p. 144. 

 Scoloplos marginatus Monro, 1936, p. 159; Monro, 1939b, pp. 123-124. 

 Scoloplos {Leodamas) marginatus Hartman, 1953, p. 38. 



The thorax consists of 11-14 or up to 18-19 segments; transition to 

 the abdomen is abrupt thereafter. The prostomium is acutely conical 

 and longer than wide. Branchiae are present from the sixth setigerous 

 segment and continue on all other segments ; they are simple and un- 

 divided. Thoracic neuropodia have uncini only. Abdominal neuropodia 

 have singly occurring yellow curved acicula that extend from the neuro- 

 podial lobe. Furcate setae are present in abdominal notopodia. 



The last six thoracic segments have a postsetal lobe at the middle of 

 the neuropodial ridge, differing in this respect from S. (L.) ohlini (see 

 above). The variety mcleani Benham (1921, p. 78) differs from the 

 stem species in that posterior thoracic neuropodia are said to have three 

 to six dark spines behind and below the uncini. 



Distribution. — Scoloplos {Leodamas) marginatus comes from Ant- 

 arctic and subantarctic regions in shallow depths to 270 fathoms. 



