NO. 2 HARTMAN : POLYCHAETOUS ANNELIDS 265 



The prostomium has an elongate palpode at its anterior end, followed 

 by a depressed ring (pi. 26, fig. 65). The first (peristomial) achaetous 

 segment is longer than wide and exceeds in length the first setiger (pi. 26, 

 fig. 64). The next 4 segments (second to fifth) are provided with only 

 capillaiy setae (pi. 26, fig. 64), including 10 to 14 setae in a fascicle. 

 The next 6 segments (sixth to eleventh) are provided with uncini (pi. 

 26, fig. 66), including 10 to 12 in a fascicle. The thoracic hooks are long, 

 those of the first few segments may extend distally almost as far as the 

 pointed setae. Dorsal hooks of the tenth and eleventh segments are dorso- 

 lateral in position but not modified as a copulatory apparatus. The 

 thoracic segments increase in length, gradually, from second to eleventh. 



Demarcation between thorax and abdomen is not distinct except for 

 a change in the epithelium from a wrinkled appearance to one that is 

 smooth, and the abdominal segments are more or less coiled. The first 

 abdominal segment is shorter than those immediately following (pi. 26, 

 fig. 64), but there is a gradual decrease in length farther back, so that 

 they come to be shorter than wide. Uncinigerous tori are somewhat 

 inflated but not conspicuous; they are provided with about 6 to 12, long- 

 handled hooks that extend distally beyond the parapodia only slightly. 

 Tori near the posterior end are more prominently elevated, but nowhere 

 conspicuous. The proboscis is a soft, glandular sack, with widely scattered, 

 low papillae (partly everted in pi. 26, fig. 65). 



M. calif orniensis inhabits sandy mud flats, at low water line, some- 

 times associated with Notomastus tenuis (above). 



Holotype. — ^AHF no. 63. 



Type locality. — Tomales Bay, California, at low-tide line. 



Distribution. — Marin and San Mateo counties, California; in mud 

 flats. 



Family Maldanidae 



Axiothella rubrocincta (Johnson) 



Clyrnenella rubrocincta Johnson, 1901, p. 418. 

 Monro, 1937, p. 310. 



This is the only maldanid known to occur in intertidal zones of 

 central California. It is a host of a commensal crab, Pinnixa longipes 

 (Lockington). It is relatively abundant on the Tomales Bay flats, inside 

 Sand Point, above beds of Phoronopsis, at midtide line, though not uni- 

 form in its occurrence at this level. It occurs at all lower intertidal levels, 

 but only a few, scattered individuals are to be found. It is rare, at low 

 tide, in mud among rocks above Dillon Beach. (Distribution record is 

 from Dr. F. A. Pitelka.) Length is 100 to 150 mm. 



