174 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.10 



In these specimens, maxilla I of the proboscis has a strongly falcate 

 tip and numerous teeth at the base, about as shown by Crossland (1924, 

 p. 72, fig. 90), hence not as shown by Chamberlin (1919, pi. 61, fig. 2), 

 in which the distal end is shown without a falcate portion ; whether the 

 latter condition is typical or the result of wear or breakage is not de- 

 terminable. 



Distribution. — Tropical eastern Pacific, from the Gulf of California, 

 south to Panama; also Easter Island (Chamberlin), Galapagos Islands, 

 and Dry Tortugas, Florida (Monro). 



Genus NOTOGIRRUS Schmarda, Ehlers revised 

 Type N. chilensis Schmarda 



The prostomium is plain, usually has 4 eyespots but lacks antennae. 

 Parapodia are provided with only simple, bilimbate setae and a heavy, 

 projecting aciculum. The proboscidial armature is much as in Arabetla 

 (above), i.e., the carriers are long, slender, with a median unpaired piece; 

 maxillae I are dentate for their entire length, lack a distal falcate tip; 

 other maxillary pieces are more or less dentate. Mandibles are propor- 

 tionately large, strong, much as in Arabella. 



Notocirrus resembles Drilonereis Claparede in having heavy, project- 

 ing acicula, and Arabella Grube, in its proboscidial parts. It was origi- 

 nally described (Schmarda, 1961, pp. 116-119) to include 5 species, but 

 has since been revised (Ehlers, 1868, p. 406) to retain only one of these, 

 N. chilensis Schmarda; the other species have been referred to other 

 genera. However, Ehlers' original revisional statement, "verkiimmerte 

 Bauch-cirrus," was later emended by him (Ehlers, 1897, p. 80). Mc- 

 intosh (1910, p. 400) again revised the genus to include A^. scoticus 

 Mcintosh (1869) from Scotland, but Fauvel (1923, p. 451) considers 

 the latter to be based partly on a Drilonereis, partly on an Arabella 

 species. 



The following species, all from the Western Hemisphere, are be- 

 lieved to belong to Notocirrus Schmarda. 



1. N. chilensis Schmarda (1861, p. 116) from Chile. 



2. A^. lorum Ehlers (1897, p. 78) from the Strait of Magellan. 



3. A^. virginis (Kinberg) (1865, p. 573) off southern South America. 

 Notocirrus zonata Moore (1903, p. 455) from Japan was described 



from a posterior end only; thus its proboscidial formula is not known. 

 Arabella attenuata Treadwell (1906, p. 1172) from Monterey Bay, 

 California, may belong here (but see p. 176). Another species, N. cali- 

 forniensis (below), is believed to be new to science. 



