148 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL.10 



Setae and acicula are clear yellow. The transition from long, slender, 

 simple hooks In anterior segments to shorter, stouter hooks occurs be- 

 tween parapodia 25 and 40. LImbate setae are practically absent after 

 segment 61, but the inferior ones are absent already from the forty-third 

 segment. Posterior parapodia are provided with only simple, hooded 

 hooks, with many small teeth distally (pi. 9, fig. 192). 



The maxillary formula for 2 Individuals (coll. 473-35 and 835-38) 

 is about as follows: forceps are falcate; maxilla II has 4 teeth on either 

 side, but a small fifth tooth may be present subdistally ; maxilla III has 

 2 teeth on either side and maxilla IV has a single tooth on either side. In 

 another specimen (coll. 1045-40) maxilla II has 4 teeth right and 5 

 teeth left, but the right piece has a notch between the third and fourth 

 teeth, suggesting a 5-5 condition. Moore (1911, p. 291) described the 

 maxillary formula as 1-1, 5-5, 2-2, 1-1 for a specimen from California. 

 Carriers are slightly longer than broad, laterally Incised, basally oblique 

 (pi. 8, fig. 190). The mandibles have very short, free basal ends and 

 flare distally (pi. 8, fig. 191). 



The numerous specimens listed above, from our collections, agree 

 well with one another In all respects save that the maxilla II may have 

 4 or 5 teeth; this Is believed to represent individual variation. In other 

 details, body proportions, parapodial parts, and proboscldial armature, 

 they are the same. The unique auricular parapodial lobes of anterior 

 parapodia, the long, digitate lobes in median and posterior segments, and 

 the distribution of hooks and setae seem to be constant features. I have 

 examined the type of L. sarsi KInberg (1865, p. 569) from Guayaquil, 

 Ecuador, and am inclined to believe that It is conspecific with L. tetraura. 

 The latter was originally described with 5 teeth on the second maxillary 

 plate, L. sarsi with only 4 teeth, but this difference may be only a varia- 

 tion. The proboscldial armature of L. sarsi is missing from the type col- 

 lection. 



As L. brevicirra, Monro (1933, p. 83) has reported an Interesting 

 form from Coiba Island, which may belong here. Its general appearance 

 was described as somewhat ragged because of the elongate postsetal lobes. 

 Through the courtesy of the late Mr. C. C. A. Monro of the British 

 Museum, I have been permitted to see this specimen. In the anterior re- 

 gion the postsetal lobe is broad, lamellar (pi. 9, fig. 193) ; it continues so 

 through about 25 segments. Thereafter It diminishes gradually in width, 

 but continues proportionately long to the end. Near the posterior end it is 

 digitlform, more or less erect (pi. 9, fig. 195). 



Ehlers' (1901, pp. 137-140) description of L. tetraura appears to be 

 partly this species and partly L. magalhaensis. These materials originated 



