NO. 2 HARTMAN : POLYCHAETOUS ANNELIDS 283 



bilimbate setae (pi. 24, fig. 53) above and short, spatulate setae (pi. 24, 

 fig. 56) in 2 transverse rows below. Neuropodia are provided with an 

 anterior row of pennoned setae and a posterior row of avicular hooks. 

 Those of the first thoracic torus number about 20 sets, those of the second 

 to third last thoracic segments number about 23 to 24 in a set, but in the 

 last 2 thoracic tori the pennoned setae and their companion hooks (pi. 24, 

 figs. 57, 58) are conspicuously fewer in number and larger, numbering 

 only 8 or 9 sets in a series. 



Abdominal segments are provided with a double row of bilimbate 

 neurosetae with a long, slender point more nearly resembling those in the 

 collar fascicle than those in other thoracic segments. Notopodia have 

 single rows of avicular hooks like those in the thorax, but they are much 

 shorter stemmed and smaller than those in front, and the comb region 

 is thick, so that the hook does not readily lie flat. 



Tubes are slender, closely fitting the occupant, externally covered 

 with small fragments of sand and shell, attached to the tube more or less 

 transversely. 



P. socialis is characterized by its small size, its reduced number of 

 radioles, its collar membranes, and its thoracic hooks, especially those of 

 the last 2 thoracic segments. In the last respect it approaches P. inter- 

 media Moore (1905, pp. 562-564, pi. 37), but the latter is a much larger 

 species, its collar membrane has high dorsal lobes, and radioles are be- 

 lieved to be totally lacking eyespots. 



Holotype. — AHF no. 68. 



Type locality. — Tomales Point, Marin County, ocean side, in sponge 

 among rocks ; intertidal. 



Distribution. — Central California. 



Eudistylia polymorpha (Johnson) 



Bispira polymorpha Johnson, 1901, pp. 428-430, pi. 17, figs. 179-183, 



pi. 18, figs. 184, 185. 

 Hartman, 1938, pp. 18, 19, 23, pi. 2, fig. 5. 



Several individuals were taken from rocky habitats at Tomales Point 

 and Dillon Beach. In life the tentacular crown is typically deep maroon, 

 tipped with pale yellow or deep orange. The dorsal edge of the tentacular 

 membrane is deeply cleft (Hartman, 1938, pi. 2, fig. 5). The collar 

 membrane is deep, much less oblique than in E. vancouveri (below). Ten- 

 tacular eyespots are black, often conspicuous. Length is over 100 mm. 



