NO. 4 HARTMAN : POLYCHAETOUS ANNELIDS 439 



few pointed setae in the superior part of the fascicle ; in other respects the 

 2 individuals are alike. Abdominal segments are unmarked except for 

 the segmental grooves and the low^ parapodial ridges. 



Lateral organs are visible on both thoracic and abdominal setigerous 

 segments, located between notopodia and neuropodia but slightly nearer 

 the former; they are small, papillar and resemble one another in anterior 

 and posterior regions. Nephridial pores are distinguishable only on the 

 thorax; they occupy a position in the segmental grooves; the first is 

 present between setigerous segments 7 and 8, the last between setigerous 

 segments 14 and 15 ; they number 8 pairs. None have been distinguished 

 in other parts of the body. No branchial structures have been identified. 



In anterior abdominal segments the notopodial tori are short and 

 dorsal in position; they are well separated from each other middorsally 

 and farther back they continue much the same but come to be shorter. 

 Neuropodial tori in the same segments are somewhat longer and ventro- 

 lateral in position. Farther back the tori increase in length so that the 2 

 of a pair approach each other midventrally. 



Hooded hooks are similar throughout. The hood is basally attached 

 in the region of the shoulder; its distal aperture is smooth and the margin 

 appears entire. The node is thick and abrupt especially on the back side. 

 The beak has a strong fang and is crowned by 3 well separated teeth 

 arranged in a triangle (pi. 54, fig. 3). The fibrilations of the core are 

 coarse. 



Holotype. — AHF no. 123. 



Type locality. — 1 mile northwest of San Gabriel Bay, Espiritu Santo 

 Island, Gulf of California, Mexico in 20-35 fms, in mud. 



Distribution. — Gulf of California and Cedros Island, western side of 

 Lower California in 29-55 fms. 



Genus PROTOCAPITELLA Berkeley 

 Type P. simplex Berkeley 



The thorax and abdomen are indistinctly separable but the separation 

 may be at about the fourteenth or fifteenth segment. Notopodia through- 

 out are provided with only pointed setae; neuropodia have long handled 

 hooks. The prostomium is a plain, rounded lobe with weakly developed 

 eyespots and a pair of nuchal slits at its posterior margin. Branchiae are 

 present as simple, palmately branched filaments in a posterior abdominal 

 region, they originate from the surface epithelium adjacent to the noto- 

 podia. Lateral organs are seemingly absent. Nephridia are limited to 2 



