NO. 4 HARTMAN : POLYCHAETOUS ANNELIDS 409 



segments are provided with hooded hooks only; thereafter neuropodia 

 have hooks only but the notopodia have both pointed setae and hooks ; far 

 posterior notopodia have pointed setae only. There are no visible 

 branchiae, lateral organs or nephridial apertures. The posterior end 

 terminates in a long caudal tail. 



Capitita differs from nearly related genera in that median and pos- 

 terior notopodia are provided with both hooks and pointed setae (pi. 45, 

 fig. 4). 



Capitita ambiseta, new species 

 Plate 45, Figs. 1-4 



Collections.— 1442A\ (about 6); 1445-42 (many); 1451-42 (4). 



There are numerous tiny, adult or mature individuals; the general 

 form is minute, threadlike, the entire length is only 12 to 15 mm and 

 width is about 0.5 mm. Total number of segments is about 70. In life 

 the body is purplish red as in most other capitellids; presei'ved it is pale. 

 The surface epithelium is smooth except for segmental grooves (pi. 45, 

 fig. 1 ) . Separation between the thorax and abdomen is not sharp, but the 

 abdomen is slightly wider than the thorax in its posterior portion and the 

 alimentary tract widens in the latter region (to be seen in translucent 

 individuals in life). 



The prostomium is slightly flattened and tapers anteriorly to a short 

 palpode ; it lacks visible pigment or eyespots. Nuchal slits have not been 

 identified. The partly everted proboscis is globular, its surface covered 

 with low papillae. The first segment or peristomium is smooth and 

 longer than those following. Segments 2 to 5 are provided with noto- 

 podial and neuropodial fascicles of pointed setae. The first setigerous 

 segment has 4 or 5 setae above, 3 to 5 below; the second has 5 or 6 setae 

 above and about the same number below; the third has 6 above and about 

 5 below; the fourth has as many or more. The next 5 segments are pro- 

 vided with only long-handled, hooded hooks in both notopodia and neuro- 

 podia; they number 6 to 11 in a fascicle and resemble those in the 

 abdomen. The eleventh segment seems to be transitional in that in its 

 length it compares with those in front, but in the position of its parapodia 

 it is like those in back. 



In the abdomen, anterior notopodia through 8 to 16 segments are 

 provided with only hooded hooks ; thereafter, the superiormost hook in a 

 fascicle is replaced by 1 or 2 slender, pointed setae. In about the last 25 

 notopodia hooks are seemingly absent ; a single, longer slightly curved seta 



