152 ALLAN HANCOCK PACIFIC EXPEDITIONS VOL. 10 



Lumbrineris simplex, new species 

 Plate 10, Figs. 224-229 



Collections.— nO-35 (1); 1053-40 (1); 1063-40 (2). 



Three specimens from the Gulf of California depart so widely from 

 other species of Lumbrineris that they are believed to represent an unde- 

 scribed one. They are large, robust ; a 350-segmented individual measures 

 180 mm long. Color (preserved) is iridescent purplish brown in the an- 

 terior fifth of the body and paler farther back ; each ring is crossed by a 

 narrow, dark, broken stripe. 



The prostomium is bluntly conical, depressed ; its length is equal to 

 that of its width at the base ; it is as dark as the anterior part of the body ; 

 no eyespots are visible. The first (apodous) ring is about as long as the 

 third, the second a little shorter. Parapodia are provided with a short, in- 

 conspicuous presetal lobe, and a longer, triangular, postsetal lobe that is 

 uniquely uniform in proportions throughout the length of the body. An- 

 terior segments, through 42 segments (coll. 1063-40) to 46 segments 

 (coll. 1053-40), have only simple, bilimbate setae. A tenth parapodium 

 has a supra-acicular fascicle of 5 larger, limbate setae and 5 subacicular 

 similar setae somewhat smaller in size. In another specimen (coll. 1063- 

 40) there are 8 limbate setae and 3 yellow acicula. The notopodium is 

 represented by a greatly reduced dorsal cirrus and an embedded fascicle 

 of numerous fine acicula (pi. 10, fig. 224). The neuropodium is support- 

 ed by 3 to 5 yellow acicula. Simple, hooded hooks are present from seg- 

 ments 43-47 to the end, partly or entirely replacing the limbate setae. 

 Acicula come to be heavier and are reduced usually to 2 in a parapodium; 

 they are yellow. Many posterior parapodia (pi. 10, fig. 226) are pro- 

 vided with only hooded hooks ; in some, however, there may be one to 3 

 limbate setae (pi. 10, fig. 225) which in size and shape are much like 

 those in anterior segments, not reduced as is often the case in other 

 species of this genus, when such setae are continued far back. Hooded 

 hooks have a larger, basal tooth and numerous fine teeth distally (pi. 10, 

 figs. 228-229). 



The proboscidial formula is much as in L. zonata (above). The car- 

 riers are longer than wide, terminate basally in slender points, and have 

 deep lateral incisions. The forceps are strongly falcate. Maxilla II has 

 5 well-defined teeth on the right side, 4 on the left side; maxilla III has 

 2 distinct teeth on either side, and maxilla IV has a single sharp tooth on 

 either side. The mandibles are heavy, fused along most of their length; 

 a short portion at the base is free; they greatly resemble those in L. 

 tetraura (above) except that the basal ends are separated for a somewhat 



I 



