120 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 15 



Distribution. — This species occurs in all Antarctic regions, also 

 southern South America to the La Plata River, and in deep water off 

 Maine (Verrill, 1874). It is recorded from littoral zones to 1200 fms. 



Aglaophamus peruana (Hartman), new combination 



Nephthys macroura peruana Hartman, 1940, p. 236, pi. 39, figs. 89, 

 90, pi. 40, figs. 96. 97. 



Collections. — (see Hartman, 1940, p. 236). 



This is referred to Aglaophamus because interramal cirri are in- 

 volute. The original subspecies is raised to specific rank since it differs 

 from Aglaophamus macroura (see above) in some major characters. 



The prostomium is broadest in front and has a thin, spatulate 

 margin that is prolonged ectolaterally as the slender, tapering frontal 

 antennae. The posterior antennae are much larger, long triangular, and 

 inserted far back at the sides of the prostomium. The posterior margin 

 of the prostomium extends medially backward as a tapering, slightly 

 pigmented raised ridge to the anterior end of the second segment. Nuchal 

 organs are located at the postectal margins where the first segment ad- 

 joins. There are no eyespots. The ventral folds of the mouth extend 

 back to the sixth segment. 



The proboscis (seen by dissection) is much like that in A. macroura 

 (above). It has 22 bifid terminal papillae, with the middorsal and mid- 

 ventral ones the smallest. There are 22 longitudinal rows in the sub- 

 terminal series, with 2 or 3 irregular rows; these abruptly give rise to 

 14 longitudinal rows with 4 or 5 in a row and each of these divides into 

 2 or 3 small papillae. The proximal surface of the proboscis is smooth. 

 There is no middorsal or midventral papilla. The paragnathal jaws are 

 horny yellow and broadly embedded. 



The first segment is longer and narrower than those farther back; 

 it is clearly biramous with numerous setae in each branch. The neuropod- 

 ium extends forward and under the notopodium; it has a large, tri- 

 angular ventral cirrus that exceeds in size the posterior prostomial 

 antennae and is considerably larger than ventral cirri farther back. 

 Neurosetae are in a larger preacicular fascicle and an inconspicuous 

 postacicular one. The first notopodium is a low mound with a minute 

 notopodial cirrus; it carries a full fascicle of preacicular and a weak 

 bundle of postacicular setae. 



Interramal cirri are first present from the third segment and partly 

 inscribe a spiral; within a few segments they are rapidly larger and 

 come to be coiled. The notopodial cirrus is broadly foliaceous and ends 

 distally in a filamentous tip. The subacicular portion of notopodia and 

 the supra-acicular of neuropodia is greatly prolonged as a digitate lobe, 



