NO. 2 HARTMAN : POLYCHAETOUS ANNELIDS 279 



2. Minute; thoracic spatulate setae with a mucron (pi. 23, fig. 52) ; 

 inhabits shell-covered tube C. minuta 



2. Large, robust; thoracic spatulate setae lack mucron (pi. 23, fig. 

 47) ; inhabits thin, sand-covered tube C. mollis 



3. Thoracic inferior notosetae spatulate (pi. 23, fig. 43) . . . 4 



3. Thoracic inferior notosetae broadly limbate (pi. 23, fig. 42) 

 Sabella media 



4. Base of tentacular crown spiraled, inrolled on ventral side, so 

 that radioles inscribe more than one whorl , . . Eudistylia 5 



4. Base of tentacular crown not spiraled, each half of crown inscrib- 

 ing only a semicircle PseudopotaTuilla 6 



5. Tentacular radioles crossed by alternating bars of red and white; 

 dorsal edge of tentacular base not cleft . . . E. vancouveri 



5. Tentacular radioles deep maroon, with pale or orange tips; 

 dorsal edge of tentacular base deeply cleft . . E. polymorpha 



6. Larger; dorsal edge of tentacular base deeply cleft; tentacular 

 eyespots number usually several on a radiole where present; 

 usually highly colored in life P. occelata 



6. Tiny; dorsal edge of tentacular base not cleft; tentacular eye- 

 spots usually one or few on radioles where present ; usually white 

 or pale in life P. socialis 



Ghone mollis (Bush) 



Metachone mollis Bush, 1904, p. 216, pi. 35, figs. 19, 20, 28. 

 Hartman, 1942, p. 87, figs. 141-143. 



Many individuals were taken from Tomales Bay, in sandy mud flats. 

 This is a stout, robust species (Hartman, 1942, p. 87). Larger individuals 

 consist of about 65 setigers and measure 63 mm long, including the 

 crown, which measures about 12 mm long (somewhat rolled inward). 

 Segments are neatly uniannulate, but have a faint transverse groove about 

 midway across each segment. The tentacular crown has a deep palmate 

 membrane, extending well over half the length of the radioles. 



The first setiger has a small, papillar notopodium, provided with a 

 reduced fascicle of pointed setae. Farther back, both notopodium and 

 neuropodium are well represented. Spatulate thoracic setae are distinctly 

 without mucron, usually with a dimple at the distal end (pi. 23, fig. 47) ; 

 all resemble one another. Thoracic uncini have a long, major tooth (pi. 

 23, fig. 48). Abdominal uncini are also characterized by a prolonged 

 major tooth (pi. 23, fig. 49). Color in life is uniformly white or some- 

 what yellowish. 



