lltj THE ANNELIDA POLYCHAETA. 



dorsal or next to the most dorsal may be stouter than the others. On the fourth 

 parapodia in the type there are many compound setae, with simple setae repre- 

 sented only by a single one near the middle and an inconspicuous shorter one 

 on the ventral side. On succeeding parapodia the nmnber of compound setae 

 much increases, as usual. The single aciculimi in each parapodium (neuro- 

 podium) is colorless, regularly tapered distad, and straight. The compound 

 setae are colorless. The shaft is straight, and slightly and imiformly clavately 

 enlarged distad, with the socket very strongly asymmetrical, one edge being 

 practically absent, or represented only by a slight angular projection on which 

 the blade rests, and the other one very long, distally rounded, and with its acute 

 tip a little recurved. Blades shorter than the exposed portion of shaft, narrow; 

 narrowed at each end as usual, with serrations exceedingly fine. (Plate 17, 

 fig. 7). 



Locality. Off southwest coast of Mexico, 28 miles S. 86° E. from Galero 

 Point: Sta. 4598 (lat. 15° 58' N., long. 98° 13' W.). 300 fms. to surface, verti- 

 cal net. Surface temp. 84° F. 15 October, 1904. Two specimens. 



The species approaches L. breve Grube, from which at once separable 

 through the absence of eyes. 



LOPADORRHYNCHUS NANS, Sp. noV.^ 



Plate 17, fig. 1-5. 



The general color at present is dusky yellow, without markings excepting 

 for a somewhat clearer median ventral fine. 



The type is 12 mm. long. The greatest width, exclusive of the parapodia, 

 is 2.5 mm.; and inclusive of the parapodia, 3.5 mm., the parapodia all bent 

 back obliquely at present. The body is widest at the middle; cephalad it 

 remains broad, decreasing in width only slightly, but caudad it narrows strongly, 

 the posterior region becoming slender. The number of setigerous somites is 

 twenty-seven. 



The prostomium is short and broad; anteriorly it is moderately convex 

 between the tentacles. The tentacles of each side are widely separated from 

 those of the other. The dorsal tentacle on each side is much longer and thicker 

 than the ventral one, the ratio in each case being nearly two to one. No eyes 

 are present. 



' nans, swimmer. 



