80 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL, 10 



tieth) ; they number 2 in a parapodium, are yellow, and typical of the 

 genus. Pectinate setae, nowhere conspicuous, are already present from 

 the sixth setiger (but in some specimens even earlier) ; they are contin- 

 ued to the posterior end, where they are not noticeably different from 

 those in front save for smaller size. Distally they have about 10 delicate 

 teeth (pi. 3, fig. 68). Limbate setae are long, slender, simple; their cut- 

 ting edge is smooth except for weak, faint crenulations. A fifty-eighth 

 parapodium is provided with 6 or 7 long, slender limbate setae, 5 or 6 

 pectinate setae, 2 yellow subacicular hooks, and 2 geniculate, pointed 

 acicula (pi. 3, fig. 72). 



The proboscidial armature is thin and delicate. Mandibles are long, 

 slender, and thin save for a calcified distal plate (pi. 3, fig. 74). Maxillae 

 are likewise thin, translucent save for dark, horny lines marking sutures 

 and articulating surfaces. The carriers and forceps together are not much 

 longer than the mandibles. Carriers together are about as broad as long, 

 basally drawn out into fine tips, slightly incised near their anterolateral 

 edge (pi. 3, fig. 73). Forceps are thin, falcate. Maxillae II to IV have 

 numerous cutting teeth, none unusually enlarged or separated from the 

 others. On the left side, maxilla II has 9 teeth, III has 9 teeth, IV has 

 6 teeth, and V has a single point; on the right side II has 8 teeth. III has 

 9 teeth, and V has a single tooth (pi. 3, fig. 73). 



Anal cirri are cirriform, include 2 longer dorsal ones, each about as 

 long as the last 20 segments, and 2 shorter ventral ones, about 1/4 as long. 



O. microcephala belongs to a group in which tridentate hooks are 

 present in anterior segments, branchiae are present from an anterior re- 

 gion and provided with numerous filaments; a few segments are provided 

 with stout, simple, tridentate hooks; composite spinigers are absent. It 

 differs from nearly related species in having a cirriform ventral cirrus 

 through only 2 segments. It is a more robust species than O. nebulosa 

 (above) and lacks the greatly elongated anterior cirri such as are present 

 in O. vexillaria (below). 



Holotype. — AHF no. 40. 



Type locality. — Punta Cholla, Sonora, Mexico, intertidal (collected 

 by Mr. Steve A. Glassell). 



Distribution. — ^Western Mexico and Gulf of California, north to 

 Anacapa Island, California; intertidal to 13 fms. 



Onuphis vexillaria Moore 



Plate 5, Figs. 90-98 



Moore, 1911, pp. 266-269, pi. 17, figs. 69-76;? Treadwell, 1934, p. 8. 



Collections.— 161-3^ (4); 1074-40 (1); 1136-40 (5); 1204-40 

 (5); 1256-41 (1). 



