ART. 15 POLYCHAETOUS ANNELIDS FROM ORIENT TREADWELL 7 



uncolored. The terminal joint is fully as long as the prostomium, 

 its filamentous apical region being nearly as long as its basal por- 

 tion. The latter narrows slightly from the base, then widens into a 

 globular swelling which is followed by the filamentous portion. It 

 is colored brown from its base to about half way up the swollen por^ 

 tion with the remainder uncolored. The ceratophore of the median 

 tentacle is about twice as wide as that of the lateral and extends 

 to a short distance beyond it. The terminal joint of the median 

 tentacle is fully twice the size of either lateral, but resembles them 

 in form though the terminal filament is relatively much shorter. 

 The bulbous portion of the median tentacle is about at the level of 

 the anterior end of the lateral ones. The two tentacular cirri of the 

 ,«ame side resemble one another in form and size and are about the 

 size of the median tentacle. They are pigmented only on a narrow 

 band just proximal to the bulbous swelling. The palps are large, 

 extending to a distance of about twice the length of the median ten- 

 tacle and taper uniformly from the base to the apex, where they end 

 in a filamentous tip. Their surfaces are unpigmented and are 

 covered with densely arranged and relatively large, " cilia." 



The body is mostly without color. On the mid-dorsal line of each 

 somite is a patch of dark pigment made up of minute transverse 

 parallel lines. In anterior somites these are darkest near the anterior 

 border of the somite extending as a diffuse patch toward the posterior 

 border. Toward the middle of the body this pigment appears as a 

 small, dark, median patch with its long axis parallel to the axis of 

 the body and a diffuse patch forming a " wing " on either side. All 

 elytra show some pigment. In the type specimen the first four are 

 faintly pigmented, the fifth to the eleventh, inclusive, intensely' so, 

 the twelfth, again, has very little color. The distribution of the 

 pigment is the same in all elytra (fig. 5), the pigmented area occu- 

 pying a little more than one quarter of the surface. It begins in the 

 form of a blunt point near the anterior end of the elytron and covers 

 the whole extent of its dorsal margin and extending inward from 

 this in a gradually widening area which abruptly ends at about the 

 level of the beginning of the pigment patch on the following elytron. 

 Under low magnification this pigment is seen to be broken up into 

 angular areas, each with a colorless spot in the center. There are 

 12 pairs of elytra overlapping one another on the same side, leaving 

 the mid-dorsal surface of the body uncovered. They are approxi- 

 mately of the same form throughout the body, have entirely smooth 

 margins, and are translucent except where pigmented. There is a 

 single row of minute spines near the latero-anterior border with a 

 few similar spines irregularly arranged elsewhere on the surface. 

 (Fig. 5.) 



