POLYCH-ETA. — BENHAM. 137 



is very short, brown, and bluntly bidentate ; the shaft is 

 transversely striated with a deep articular cup (PI. xlvi., 

 fig. '8). 



In the anterior feet the dorsal bundle contains only a few 

 (2-4) homogomph spinigers, the appendix long, with extremely 

 fine denticulations. The change in the character of these 

 chsetae occurs on or about the 22nd segment. 



The ventral supra-acicular bundle contains also four homo- 

 gomph spinigers, two of which have long and two shorter 

 appendices. Below are four heterogomj^h falcigers, the shaft 

 of which is thick and striated ; the appendix is moderately 

 long, setose along the edge, and with a feeble terminal hook 

 (PI. xlvi., fig. 9). The sub-acicular bundle contains four 

 heterogomph spinigers, with a short appendix, and two or 

 three heterogomph falcigers. 



In all the spinigers, dorsal and ventral, anterior and 

 posterior, the appendix is the same in form though it may 

 differ in length in the same bundle. 



In the first two feet, which as usual have only the neuro- 

 podial lobe, all the chsetse are spinigers ; the upjjer bundle 

 has two homogomphs and two heterogomphs with a short 

 appendix ; those of the lower bundle are heterogomphs. 



The jaws. — The maxilla has nine blunt denticulations, and 

 like the rest is pale brown. 



The paragnaths are very pale, rounded cones (PI. xlvi., fig. 

 10). The formula is :— 



I. Absent. 



II. 5 or 6, forming an ovol group. 



III. Absent. 



IV. A transverse curved group of about 8 denticles. 



Remarks. — At first I supposed that this worm was different 

 from C. falcaria, as it diflers in three points from the few 

 details given by Willey : firstly, in the segment at which the 

 change of chaeta? begins, which is the 17th in the Ceylon 

 worm ; secondly, in the absence of denticles in the area 

 III. ; and, thirdly, in the number of denticulations on the 

 maxilla, which Willey states to be only six. It may very 

 likely prove that some of these features are variable. The 

 denticles, for instance, in my species are very pale, and their 

 absence in III. may be due to their having fallen away ; while 



