KAINONEREIS ALATA. 201 



little notched on each side toward the base where the corresponding edge of the 

 socket meets it, the piece being thus loosely clamped in place. Along one side 

 it is closely, finely setose. In the most anterior parapodia these setae may not 

 be above two in number, but the number increases to three or fouJr in the para- 

 podia bearing the elytra. Behind these the dark special setae just described 

 are replaced by setae like those of the neuropodia. (Plate 28, fig. 8). These are 

 colorless and transparent and are clearly more slender than the dark anterior 

 notopodials. The shaft is more strongly curved distad and ends in a socket 

 that is more asymmetrical, one of its sides rising considerably higher than the 

 other, but still more conformable to the homogomph than to the heterogomph 

 type of Claparede (Annelides Chetop. Golfes Naples, Suppl., 1870, p. 42). The 

 distal end of the shaft is a little clavately enlarged. The shaft is strongly cross- 

 striate, the striations commonly in two contiguous bands. The terminal piece 

 is narrow, moderately short, and narrows to an acute tip. It is closely, finely 

 setose along one edge. It varies in length, that of the most dorsal ones in the 

 series being longest. While the neuropodial setae in the anterior parapodia 

 much exceed the notopodials in number, behind the elytra the notopodials in- 

 crease in number until they much exceed the neuropodials in the posterior part 

 of the anterior series and in some succeeding oens of the second series. Begin- 

 ning with the twelfth parapodia, this second type of setae is abruptly replaced 

 both on notopodia and on neuropodia by a thii-d type differing especially in 

 being larger and in having the terminal piece much larger and broader, more 

 paddle-like, widening from the base to distad of the middle, and then again 

 narrowing to the acute or subacute tip. The terminal piece along one edge is 

 very finely and shortly serrate. (Plate 29, fig. 6). Some of the notopodials, e.g., 

 those of the twelfth parapodia, have much shorter terminal pieces, which, 

 however, are the same in structure as the others; they are in the more dorsal 

 position. The number of setae, both neuropodial and notopodial, much 

 increases toward the middle of the body, where also inequality in the number of 

 setae in the two rami becomes less or not at all noticeable. 



The pharynx is straight. The oesophagus is similarly straight. It is 

 abruptly much narrower than the pharynx and bears at its anterior end the 

 usual pair of simple caeca. (Plate 29, fig. 8). The proboscis in no case is 

 extended. The jaws are colorless, relatively long and slender, each ^vith eight 

 teeth. Other armatm'e was not detected in the specimen dissected. 



Locality. Gilbert Island: off Apaiang. Surface, by electric light. 3 

 January, 1900. About twelve specimens. 



