NO. 4 HARTMAN : POLYCHAETOUS ANNELIDS 407 



widely in the nature of their habitat; C. ovincola is known only from 

 squid egg masses whereas C. capitate inhabits fine black silt in littoral 

 zones. 



I am indebted to Mr. and Mrs. G. E. MacGinitie for the collection 

 on which this species is based. 



Holotype. — AHF no. 118; paratypes in the Allan Hancock Founda- 

 tion. 



Type locality. — Monterey Bay, California, in 30 to 40 fms, in gel- 

 atinous masses of squid eggs. 



Distribution. — Monterey Bay, California. 



Gapitella dizonata Johnson 



Johnson, 1901, pp. 415-416, pi. 11, figs. 119-121. 



No collections are available, and the type and only known specimen 

 is not known to exist. The species was described from a single, incom- 

 plete individual, presumably an immature female that was collected 

 from intertidal zones at Port Orchard, Washington. The original and 

 only account (Johnson, 1901, pp. 415-416, pi. 11, figs. 119-121) is not 

 clear on all points. The first 7 segments have pointed setae only, and 

 such setae are continued posteriorly in notopodia through at least the first 

 abdominal segment but are thereafter replaced by hooks. However, ac- 

 cording to the account "dorsal setae of the eighth and ninth somites appear 

 to be entirely wanting." There are thus 7 segments with setae above and 

 below, followed by 2 segments lacking notopodia but having hooks in 

 neuropodia; the first abdominal segment has setae in notopodia and hooks 

 in neuropodia. 



If these stated characters are typical, C. dizonata is at once distinct 

 from other species of the genus even though additional details are lack- 

 ing. It may be suggested, however, that if the description was actually 

 based on an immature male individual in which the modified genital hooks 

 of the eighth and ninth segments either had not yet developed or had 

 been retracted, the species may prove to be conspecific with another 

 known form, possibly Capitella capitata (see above). The uncertainty 

 seems difficult to clarify unless the holotype or topotypes can be examined. 



Genus MEDIOMASTUS Hartman 

 Type M. califomiensis Hartman 



The thorax consists of 1 1 segments, of which the first lacks parapodial 

 parts ; segments 2 to 5 have pointed setae only and segments 6 to 1 1 are 



