104 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 22 



occupy a supra-acicular position, where they number 4 to 7 in a fascicle. 

 They are accompanied by simple hooded hooks in an inferior position in 

 the fascicle. 



The jaws, seen by dissection, consist of mandibles and maxillae. 

 Maxilla I is falcate; II has 5 teeth on a side, with the teeth subequal ; 

 III and IV each have a single tooth. The mandibles are fused along 

 their medial length and have a deep distal notch at the anterior or widest 

 part. 



Parapodia are lateral throughout; those of anterior segments have 

 broad, short lobes, with the pre- and postsetal lobes about equally long, 

 but the posterior one the slenderer. In the posterior region the pre- and 

 postsetal lobes elongate and are distally divergent; they resemble those 

 of Lumbrincris calif orniensis (Hartman, 1944, pi. 12, fig. 260). Long, 

 slender, simple hooded hooks are present from the first parapodium, 

 accompanied by limbate, distally pointed setae. The number of hooks 

 increases so that within a few segments they are equal in number to the 

 pointed setae. The hooks occupy the middle of the series and the longer, 

 pointed setae are at either end. At segment 12 to 14 the pointed setae are 

 abruptly longer and hairlike, and after segment 30 they are nearly absent. 



Acicula are pale translucent in their distal parts, and fuscus to nearly 

 black in their deeply embedded portion ; they number 3 or 4 in a para- 

 podium and terminate distally in a greatly attenuated tip, protruding 

 from the tapering parapodial lobes like thick needles. At first sight, they 

 look like a kind of modified seta, but their bases can be seen to extend far 

 into the parapodial base, a characteristic of acicula. 



Lumbrincris longensis is chiefly characterized by having long hairlike 

 setae in some median segments; composite hooks are absent; posterior 

 parapodial lobes are bilabiate, having both pre- and postsetal lobes elon- 

 gated. Acicula terminate distally in needlelike points and project from 

 parapodia. 



L. longensis differs from L. moorei (see above), which also has long, 

 hairlike setae in some median segments, in that these setae are in the 

 middle, not the inferior position in the setal fascicle. It differs from 

 L. bifilaris (Ehlers) (see Hartman, 1944, p. 153) which has the first 

 55 segments provided with long pointed setae in a superior position. 



L. longensis has been taken only in Long Basin ; it is presumed to be 

 an abyssal form which may have its more extended distribution in deeper 

 ocean bottoms off California. 



