LEODK'E SEGREGATA. 239 



of rather numerous, slender, colorless, simple capillary setae. These appear 

 flattened, distally slenderly pointed, and straight or slightly curved. Among the 

 capillary setae are the shorter delicate pectinate setae; each of these presents 

 the usual clavately expanded distal end which is finely toothed along its free 

 edge and at one angle bears the usual marginal process which may be conspicu- 

 ously curved outward, but is often straight. (Plate 54, fig. 2). Below these are 

 the compound setae; these are stouter than the capillary setae; they are pale 

 yellow in color; each is composed of a shaft, which is straight or nearly so, and 

 is moderately enlarged distad, and of a bidentate appendage covered as usual 

 by a delicate guard. On the middle and posterior segments crochets appear; 

 these are stout, distally narrowed and moderately curved; the principal tooth 

 of each is very stout and at its tip is slightly curved toward axis; the usual 

 terminal tooth is slightly curved toward the other tooth; its tip is about on a 

 level with that of the principal one. (Plate 54, fig. 3). 



Masticatory plates of mandibles hard, white, their anterior edge wavy and 

 the ectal angle acutely produced; stems of mandibles blackish, stout, straight, 

 and a little divergent ; the halves firmly united anteriorly by an isthmus. Maxil- 

 lae I (forceps-jaws) with basal pieces, or carriers, longer than wide; each with 

 outer edge nearly straight and subparallel to inner edge, ectocaudal angle widely 

 rounded and the caudal edge within rounded portion straight, the ectocephalic 

 angle curved ectocephalad; the forceps stout, falcate in form, as usual, black- 

 ish. Maxillae II strongly chitinized, black; left outer plate with seven large 

 teeth. The unpaired piece with ten much smaller teeth. Structure of other 

 pieces not determined in type. In a paratype from Sta. 3417 the left plates 

 of Maxillae II have respectively eight and ten (eleven) teeth, the right piece 

 nine teeth; maxillae III have nine teeth. (Plate 54, fig. 1). 



Color in general dark brown, but the dorsum with a conspicuously contrast- 

 ing, paler, yellow band along each side above parapodia, the parapodia and con- 

 tiguous parts, including the cirri and branchiae, being of the same lighter color; 

 the dorsum anteriorly and much of the venter has a reddish cast to the brown, 

 but caudally the color becomes somewhat ferruginous. 



Locality. Off Panama: Sta. 3354 (lat. 7° 9' 45" N., long. 80° 34' W.). 

 Depth 322 fms. Bottom of green mud. Bottom temp. 39° F. 23 February, 

 1891. One specimen. 



Off Panama: Sta. 3358 (lat. 6° 30' N., long. 81° 44' W.). Depth 555 fms. 

 Bottom of green sand. Bottom temp. 40.2° F. 24 February, 1891 . One specimen. 



Off Mexico: Sta. 3417 (lat. 16° 32' N., long. 99° 48' W.). Depth 493 fms. 



