1923] NATURAL SCIENCES OF PHILADELPHIA 187 



green mud and coarse gray sand; 44G1, Point Pinos Lighthouse, 

 285-357 fathoms, green mud, 4508, same locality, 292-35() fathoms, 

 soft green mud; 4517, same locality, 750-766 fathoms, green mud 

 and sand. 



CIRRATULIDAE 

 Audouinla luxuriosus (Mooro) 



Setae and cirri })egin on 1\. The dorsal gills on VII, VIII and 

 IX appear to be rather more numerous than on the type but are 

 so crowded and tangled that the number cannot be exactly deter- 

 mined. Neuropodial capillary setae are replaced at LXV by three 

 black spines, transition spines appearing on several preceding 

 segments. Throughout the middle and posterior region, there is 

 a single (rarely 2) very stout })lack spine. Si)ines more highly 

 developed than in the type, appearing farther forward and on 

 caudal segments unaccompanied by capillary setae. In the noto- 

 podia the change to spines is much less abrupt and complete. 

 They remain smaller, paler, rarely reduced to a single one (usually 

 two or three) and are usually accompanied by one or more capillary 

 setae. 



A single large specimen from station 4496, off Santa Cruz Light- 

 house, 10 fathoms, fine gray sand and rocks. 



r Tharyx multifilis Moore. 



One poorly-preserved regenerating example 30 mm. long bursting 

 with eggs. Segments 88. 



Peristomium triannulate, achaetous. Prehensile grooved tentacles 

 arise dorso-Iaterally from the furrow ])etween the peristomium 

 and first setigerous somite. Remaining somites all setigerous. 

 Branchial filaments all detached, but the scars present on a great 

 many segments immediately in contact with the notopodia. 



Station 4461 , off Point Pinos Lighthouse, 28o-323 fathoms, green 

 mud. 

 Tharyx gracilis sp. nov. Plate XVII, fltis. i, 2. 



Head region (Plate XVII, fig. 1) generally similar to that of T. 

 riiuUiJll}.^, but much more elongated and slender and the dorsal 

 surface of the peristomium thickened and slightly raised above 

 the general surface, appearing as a sort of nuchal coiie reaching 

 to the prehensile tentacles. A quadrate ventral area, defined 

 anteriorly by a transverse groove on the prostomium. bounds the 

 mouth in front, while beiiind and laterally the peristomium forms 

 its boundary. 



Metastomium a])proxiniat('ly terete with a faint neural groove, 

 tapering regularly and nearly eciually l)otli ways from the middle 

 region; the ventral surface smooth. Segments quite simple, very 



