252 PROCEEDINGS OF THE ACADEMY OF [Vol. LXXV 



a length of about 3-4 times the diameter. Barbs numerous, short 

 and crowded, the longest toward the distal end about equalling 

 the naked tip. 



Thoracic region broad and depressed, with segments of the usual 

 form. Mantle ample and prominent with a regular margin, the 

 ventral lobe, which is reflexed and reaches to IV, separated com- 

 pletely from the lateral lobes by incisions which cut to the base. 

 Lateral lobes especially high at the antero-dorsal angles and gradu- 

 ally diminishing caudad, including the first four setae fascicles and 

 ending behind the fourth. Abdomen slender and elongated, 

 slightly depressed, anterior segments about as long as wide and 

 indistinct, becoming more depressed and crowded and at the same 

 time more distinct posteriorly and ending in a minute pygidium. 



Thoracic parapodia consist of flattened dorsal setigerous tubercles 

 and ventral lappet-like tori. Collar fascicle small and directed 

 somewhat forward. Remaining fascicles much larger, more spread- 

 ing and directed chiefly dorsad and laterad, the first four included 

 in the mantle at the level of the collar setse, the last (on VI) free, 

 more widely separated and more ventral. The tori are free lappets 

 overlapping caudad; the first (on II) quite small, the others be- 

 coming successively larger, more imbricated and more ventral in 

 position until the last becomes a broad plate with rounded free 

 margin equal to the depth of the body, overlapping the setigerous 

 tubercle above and in contact with its fellow below. Abdominal 

 parapodia are very small and indistinct, both setigerous tubercles 

 and tori being obscure at the caudal end where, without being 

 larger, they stand out more distinctly. 



Small distinct glandular ventral plates occur on somites V-VIII, 

 the last being concealed by the tori of the same segment. 



The small compact collar fascicle is composed of colorless setse 

 in two rows. Those of one row are shorter, straight and strictly 

 capillary; of the other longer, curved and slightly winged. Re- 

 maining thoracic fascicles larger, more spreading, of three rows, 

 one of small, strictly capillary, the other two of narrowly limbate 

 setse, one row of the latter being like the limbate collar setae and 

 of the other shorter and slightly sigmoid. Abdominal fascicles 

 reduced to 2-4 very delicate pennoned setse. Thoracic uncini 

 colorless, numerous, 122 on V. They have the form shown in figure 

 48 but with usually only 12 or 13 teeth. Abdominal tori bear 

 fewer uncini (60 on XXXV) which are smaller (fig. 48), with 13-15 

 teeth but otherwise quite like the thoracic. Setse at the caudal 

 end are broken so that it is uncertain if some are capillary. 



Except for the brown opercular cap and a dorsal area of reddish- 

 brown at the caudal end all parts of the preserved worm are colorless. 



A small fragment of tube taken off of this specimen is whitish 

 with very irregular rough surface but no distinctive markings. 

 A piece of tube from another much smaller specimen having only 



