NO. 5 HARTMAN : POLYCHAETOUS ANNELIDS 497 



podia are provided with dorsal cirrus, one or a few notoacicula and strong 

 acicular spines that emerge dorsal to the dorsal cirrus (pi. 61, fig. 4). 

 The second parapodium has or lacks (pi. 61, fig. 3) a ventral cirrus. 

 Neuropodia are provided with ventral cirrus, one or 2 embedded acicula 

 and full fascicles of neurosetae of a single kind or including also furcate 

 setae (pi. 62, fig. 7). The posterior end terminates in a pygidial ring 

 with terminal anal aperture and (at least in some species) a pair of cirri- 

 form processes inserted ventrally (pi. 62, fig. 2). In so far as known 

 the habitat is a sandy bottom, in shallow to abyssal depths. 



The genus Ancistrosyllis is known through the following species. 



A. Those in which antennae and peristomial cirri are short : 



1. A. groenlandica Mcintosh (1879, p. 502) from Davis Strait, 

 Greenland in 410 fms 



2. A. cingulata (Korschelt) (Fauvel, 1923, p. 251) from the Medi- 

 terranean Sea, based on a pelagic larva 



3. A. albini Langerhans (1881, p. 107) from the Canary Islands. 

 (This may be identical with A. cingulata.) 



4. A. gracilis Hessle (1925, p. 34) off Japan in 300 meters 



5. A. rigida Fauvel 



B. Those in which antennae and peristomial cirri are long: 



6. A. constricta Southern (1921, p. 573) from Chilka Lake, India 



7. A. robusta Ehlers (1908, p. 59) south Atlantic Ocean in blue 

 mud 



8. A. tentaculata Treadwell (1941, p. 1) off Long Island, New 

 York 



9. A. bassi, new species 



Key to Species 



1. Prostomial antennae and peristomial cirri short, fusiform . . 2 



1. Prostomial antennae and peristomial cirri long, cirriform . . 5 



2. Integument papillated 3 



2. Integument smooth or nearly so 4 



3. Dorsal cirri of the first setigerous segment much larger than those 

 following; prostomium with a pair of large, lateral eyes . 



. A. groenlandica 



3. Dorsal cirri of the first setigerous segment resemble those farther 

 back ; prostomium with 4 smaller, dorsal eyes arranged in a trape- 

 zoid .......... A. gracilis 



4. Posterior dorsal hooks straight or nearly so (pi. 62, fig. 3) ; cirri 



