LEODICID^ OF THE WEST INDIAN REGION. 



99 



Lumbrinereis paucidentata, new species. 



(Plate 9, figures 1 to 4; text-figures 357 to 364.) 



Only one specimen was obtained. It is a small species, having a peristomial width 

 of 1 mm., a body- width of 2 mm., and contains approximately 200 somites. Its general 

 appearance and especially its jaw structure are so different from anything else that I 

 have no hesitation in founding a new species on this one specimen. 



In life the anterior region is a bright scarlet, shading into yellow posterior to the 

 fifteenth somite (plate 9, figures 1 and 2). Through a part of the intestinal region the 

 color is olive-brown with a greenish dorso-median patch in each somite (plate 9, figure 3), 

 while posteriorly it is reddish yellow (plate 9, figure 4). The prostomium is acutely 

 conical, its length a trifle greater than its width (plate 9, figure 2). The first two somites 

 are not sharply separated dorsally, but this line is more distinct laterally. On the ven- 

 tral surface the first somite is broken by the anterior prolongation of the second, as is 

 characteristic of this genus, and there is one pair of rather prominent lips. Parapodia 

 begin on the third somite and are prominent from the beginning. There are two pairs 

 of stout anal cirri (plate 9, figure 4), the ventral about one-third larger than the dorsal. 



The maxilla (text-figure 357) has a short and relatively very broad carrier (the apex 

 had been lost in the one figured) with short and relatively broad forceps. The proximal 

 paired plates have each a row of about 5 protrusions along the edge, which are hardly 

 large enough to be called teeth. There are two pairs of distal plates, each plate of a 

 semicylindrical form, with no definite teeth. The view here shown represents about 

 one-half of the semicylinder. The mandible (text-figure 358) is very unusual in form, 

 being scarcely longer than broad and with the two parts united practically along their 

 entire margins. Both ends are marked with concentric brown lines, those at the 

 anterior end being the more prominent. 



The first parapodium (text-figure 359) is relatively large and has a long, cylindrical 

 posterior lobe. It carries a tuft (there were four in the one drawn) of long, simple setae, 



TEXT-FIGURES 357 to 364. 

 Lumbrinereis paucidentata Tread well. 



357. Maxilla x34. \ 



358. Mandible x34. 



359. First parapodium x54. 



360. Compound seta x!94. 



361. Smaller anterior simple seta x!94. 



362. Larger anterior simple seta x!94. 



363. Posterior simple seta x!94. 



364. Tenth parapodium x54. 



