164 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 10 



258), but the presetal portion is reduced. A fifth parapodium is provided 

 with 3 superior limbate setae, 3 composite, hooded hooks, and 2 inferior 

 limbate setae, together with 3 yellow acicula. Farther back, the lobes 

 enlarge so that by the twenty-fifth the presetal lobe comes to be nearly as 

 long as the postsetal, but both are broadly rounded (pi. 12, fig. 259). 

 By the ninety-eighth setiger the postsetal portion has become larger and 

 longer, but both lobes are still comparatively short. After the one-hun- 

 dredth segment both presetal and postsetal portions come to be long, 

 nearly equally bilingulate (pi. 12, fig. 260). 



Composite hooks (pi. 12, fig. 261) are present from the first to about 

 the twenty-fourth to thirtieth setiger, or a little beyond. Among 9 speci- 

 mens examined, one had composite hooks through 24 segments, 2 through 

 26 segments, 5 through 29 segments, and one through 34 segments. Those 

 in the first few segments are slenderer and have a longer appendage than 

 those farther back, but even in transitional segments (between setigers 

 25 and 27) the appendage is still fairly long (pi. 12, fig. 261). By the 

 twenty-sixth parapodium, or shortly thereafter, the composite hooks are 

 more or less completely replaced by simple hooks (pi. 12, fig. 262) re- 

 sembling the composite ones in size and form but lacking the articula- 

 tion. Farther back the simple hooks have a shorter hooded region, but the 

 toothed edge of all is about the same, provided with a major blunt tooth, 

 2 or 3 smaller ones, and a series of minute dentations. Limbate setae are 

 present through a long region, but are practically or entirely absent by 

 the one hundredth parapodium, or before. 



The proboscidial armature is not unique ; the mandibles have slender 

 basal ends, flare broadly to a dark, but somewhat calcified, cutting edge. 

 The maxillae have large carriers that are longer than broad and laterally 

 incised. Maxillae I (forceps) are falcate; maxillae II have 4 teeth on 

 either side, the distalmost tooth the largest; maxillae III and IV have 

 each a single tooth. 



L. calif or niensis has affinities with L. quasibifilaris Monro (1937, p. 

 297) from the Gulf of Aden, in which the following characters also are 

 present. Composite hooks are present from the first parapodium, contin- 

 ued through a considerable anterior region; acicula are black; posterior 

 parapodial lobes are strongly bilabiate. L. calif orniensis, however, diflers 

 in that the prostomial lobe is short, not long lanceolate; the bilabiate 

 parapodial lobes are developed only after about the one-hundredth seg- 

 ment, not already by the twenty-sixth; the posterior lobe of anterior 

 parapodia is auricular, not cirriform. The proboscidial armature was not 

 described for the specimen from the Gulf of Aden. 



