228 PROCEEDINGS OF THE ACADEMY OF [Vol. LXXV 



definite lateral incisions, the only interruptions being the anterior 

 median opening through which the small, tongue-like palpode 

 projects and the faint irregular notches, or in one specimen crenu- 

 lations, which correspond with the cross-furrows on the disk. 

 No true median carina, the well defined area of one-fifth of the 

 width of the disk between the nuchal organs being not at all elevated. 

 Nuchal organs well defined, one-fourth length of cephalic plate, 

 with exception of a slight curvature at anterior end almost per- 

 fectly straight. Mouth a relatively small slightly crescentic slit, 

 far forward near end of head, with raised slightly rugous lips. 



Somite II cylindrical, about one-fourth longer than head, 

 diameter one-half length, smooth, undivided into annuli and lacking 

 conspicuous glandular areas. The next three segments are evi- 

 dently contracted and distinctly shorter than II; VI is longer than 

 V and VII still longer, equalling II; VIII equals the head and II 

 combined; IX and X are united, without dividing furrow^; XI is 

 slender and much elongated, approaching the combined length of 

 IX and X. Two other specimens agree with the type in these 

 proportions; a fourth has the posterior somites more elongated 

 and the furrows obsolete after VIII/IX. All segments are uniannu- 

 lar. From III to IX, they have proparapodial glandular zones, 

 those on VII and VIII being best developed. Somite V bears a 

 high membranous collar which closely embraces IV and except 

 for slight emarginations (which in one specimen become distinct 

 notches) at the level of the seta fascicles are quite entire and of 

 even height. On another specimen faint lateral and ventral 

 impressions give the collar a slightly trilobate character, the dorsal 

 lobe being a little the longest. Somites III, IV, VII, VIII and to 

 a slight degree IX, exhibit false collars due to the retraction within 

 their anterior ends of the preceding segments. These folds are 

 thicker and evidently double reduplicatures of the skin instead of 

 true collars. 



Although more or less indicated on all anterior segments, pro- 

 parapodial glandular zones are conspicuously developed on VII, 

 VIII and IX only; on these they are complete and occupy the entire 

 region cephalad of the setae. 



Definite parapodia are lacking on II, III and IV, which bear a 

 dorsal tuft of sessile setae and a single stout ventral spine each. 

 Remaining somites bear tori, which from V to IX inclusive, are 

 anterior and on succeeding somites posterior in position. Each 

 bears a long row of crochets occupying as much as one-fifth or 

 even one-fourth of the circumference and dorsal to it a flattened 

 lappet with a prominent tuft of setae. The number of crochets 

 varies from 9 to 14 on V, is about 30 on VIII to X, and 40 or more 

 on XII. 



On II to IV, the setae are arranged in a vertical line of two ranks, 

 one of small and one of longer slender, capillary, narrowly bilim- 



