178 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.10 



12. D. pinnata Treadwell (1921, p. 110) from the West Indies. 



13. D. quadriciispis Grube (1878, p. 100) from Desterro, Brazil. 



14. D. similis Treadwell (1921, p. Ill) from the West Indies. 



15. D. spatula (Treadwell) (1911, p. 6) from Florida. 



16. D. tenuis (Ehlers) (1901, p. 145) from the Strait of Magellan. 

 Three of the above, D. heterognatha, D. interfnedia, and D. qiiadri- 



cuspis, originating from Brazil, are very inadequately known. Seven 

 others, D. attenuata, D. hrunnea, D. debilis, D. longa, D. pinnata, D. 

 similis, and D. spatula, have been reported from the West Indian region 

 alone, but the relations of all these to one another are not at all clear. 

 D. longa Webster differs from others in that parapodia in a far posterior 

 region are uniquely bilabiate, both pre- and postsetal lobes about equally 

 prolonged. I have collected numerous examples at Beaufort, North Caro- 

 lina, in sandy shoals at low water. In life it is bright pink to red, very 

 long, slender, stringlike, breaking up when slightly pulled. D. magna 

 Webster and Benedict also inhabits sandy shoals at Beaufort, North 

 Carolina, but is a much more robust species; here the parapodial base is 

 stout, large, the postsetal lobe comparatively small, short, triangular. 

 Setal fascicles, at least in an anterior region, are heavy, with 10 or more 

 bilimbate setae in a bundle, in addition to the heavy, yellow aciculum. 



Three species, D. nuda, D. falcata, and D. filum, are represented in 

 the collections. 



Key to Species of Drilonereis 



1. Mandibles absent D. nuda, p. 178 



1. Mandibles present 2 



2. Maxillae I (forceps) without dentations at base; mandibles 

 longer than broad D. filum, p. 180 



2. Maxillae I with dentations at base; mandibles short, broad, 

 proportionately small D. falcata, p. 179 



Drilonereis nuda Moore 

 Plate 13, Figs. 297-302 



Moore, 1909, pp. 254-256, pi. 8, figs. 21-23; Monro, 1933, pp. 86-87, 

 fig. 35. 



Collections.— 90^-?,9 (1); 910-39 (1); 1159-40 (1); 1210-40 (5); 

 1211-40 (1); 1251-41 (1); 1283-41 (1); 1289-41 (1); 1442-41 (2); 

 1446-42 (2). 



D. nuda is typically a very long, slender, almost cylindrical species, 

 dark purplish in life and strongly iridescent. A specimen from Mission 



1 



