400 THE ANNELIDA POLYCHAETA. 



two, or, less commonly, three, irregular transverse rows on each segment, becom- 

 ing fewer caudad, there being on somites toward the caudal end usually but one 

 transverse row. The tubercles are highest and most crowded in the widest 

 region of the body, becoming lowest and sparsest in the caudal region. There 

 are no tubercles on the sides of the body between the parapodia. The venter 

 is also wholly smooth. 



Neuropodial setae somewhat reddish brown, inserted in a prominent tuber- 

 cle, the fascicle usually consisting of four setae. These setae are relatively 

 short, being shorter than the somite to which they pertain, and the most ventral 

 one commonly abruptlv shorter than the adjacent one, the others ordinarily 

 differing but little, or decreasing a little from the most dorsal ventrad. They 

 are straight, or but slightly curving distally. Annuli of setae moderate in length, 

 shortest proximally, often a longer annulus occurring at intervals between 

 those of ordinary length. (Plate 68, fig. 4). Notopodial setae pale, much longer 

 and much more slender than the neuropodials, straight, or a little curving in 

 the very fine distal region, Annuli long, longest at the distal end, as shown in 

 the figures. (Plate 68, fig. 5, 6). 



Locality. Off Mexico: Sta. 3417 (lat. 16° 32' N., long. 99° 48' W.). 

 Depth 493 fms. Bottom of green mud. 11 April, 1891. 



This species suggests B. mammilata Grube, occurring at Kerguelen and 

 other far southern localities. The present species is a larger form, with more 

 numerous segments and larger dorsal papillae. The neuropodial setae are 

 fewer in a fascicle, relatively shorter, with annuli conspicuously longer. 



Brada irenaia, sp. nov.^ 



Plate 68, fig. 7-9; Plate 69, fig. 1-3. 



Body consisting of forty or forty-one setigerous somites. The type-speci- 

 men, in which the prostomium is extended, is narrowest anteriorly, a little 

 constricted at the second and third somite, then widening gradually to about 

 the twelfth setigerous somite, remaining then of uniform width, or narrowing but 

 little, to about the thirty third somite, from where it narrows moderately to the 

 rounded caudal end. Segments of median region longest. Dorsal surface 

 strongly convexly arched. Ventral surface between parapodia flattened, more 

 strongly so caudad, and over the caudal third of length showing a median longi- 

 tudinal furrow. Total length, about 44 mm. Greatest width, near 5 mm. 



* tipr)vaLOS, pacific. 



