252 THE ANNELIDA POLYCHAETA. 



cirrus; in some cases in the posterior region the fibers are brownish. Setae of 

 the usual four kinds. The dorsal setae are fine, cylindrical, and acutely pointed, 

 strictly capillary and not at all limbate. Among these are the dehcate, trans- 

 parent, pectinate setae which are more numerous than usual. These have 

 exceptionally long stalks. The appendages are rather narrowly cuneate; the 

 teeth are extended into filaments which often curl toward the middle of the 

 series and in some increase progressively in length from one end of the series to 

 the other. (Plate 57, fig. 8). The compound setae, composing the conspicuous 

 ventral fascicle, are much coarser than the other ones. Each presents a decidedly 

 curved shaft which is conspicuously clavately widened distad. The shaft at 

 its wider distal portion is strongly obliquely striate as usual. The distal divi- 

 sion, or appendage, of the compound setae widens a little above the narrowed 

 basal portion by which attached, and then narrows gradually distad ; presenting 

 a moderate subbasal angle but with no distinct tooth at that level; at the distal 

 end is a suberect, moderately curved, terminal tooth or hook, below which is 

 the larger subapical tooth projecting at right angles to the axis of the appendage. 

 The edge of the transparent membranous guards is proximally straight or shghtly 

 incurved and finely, closely serrulate, bulging out above the subapical tooth 

 and extending distinctly over and above the apical tooth; obliquely striate. 

 (Plate 57, fig. 9). The crochets begin in the parapodia of the twenty ninth 

 somite. These are stout, black, aciculiform setae extending obliquely across 

 acicula proper in an ectoventral direction, with the tip emerging near the base 

 of the ventral cirrus. Each as a whole is strongly curved, with the concavity 

 ectad, the apical portion becoming straight or shghtly curved in the opposite 

 direction; at the tip are two bluntly rounded teeth covered, as usual, by the 

 membranous guards. (Plate 58, fig. 1). 



Maxillae light brown, black edged, not heavy. Maxillae I with plate 

 formed by fused carriers, acutely notched behind, convex on each side, moder- 

 ately narrowed distad, and then again widening; narrowly acutely incised 

 along middle line anteriorly with a narrow furrow connecting anterior and 

 posterior incisions; each half of plate concavely depressed. Each blade has 

 the ordinary falcate form, moderately narrowed distad, with the tip bluntly 

 rounded, upper surface nearly flat, or somewhat concavely depressed from side 

 to side, the margins being more or less elevated. (Plate 58, fig. 3). Maxillae II 

 with outer edge proximally elevated but not reflexed, or at most only very nar- 

 rowly so; on right side with seven teeth, on left with six, decreasing in size 

 proximad, the last being very small, all in type apically rounded; proximad of 



