332 THE ANNELIDA POLYCHAETA. 



developed, one being short and not surpassing the tip of the seta, while the other 

 one, attached on the opposite side, is very much prolonged beyond it and is 

 narrowed distad into a slender tip. (Plate 61, fig. 6, 7). How far forward the 

 crochets extend was not satisfactorily determined. 



There are five pairs of maxillae, which are all dense black in color. In 

 maxillae I the carriers are clavately widened at the anterior end, narrowing 

 strongly caudad into very long, slender, chitinous spines which in situ extend 

 back into the tenth somite and narrow very gradually, parallel, or nearly so; 

 each spine appearing a Uttle incurved just caudad of the expanded end, where 

 the two come in contact. The dentate plates are large, subtriangular, with the 

 apex cephalad, unsymmetrically developed; the left plate is broader than the 

 right and bears teeth along its entire mesal edge as present in the type, though 

 it appears broken off at the distal end and may in that part have had a smooth 

 edge; these teeth are large, retrorse, and eight in number; the right plate with 

 eight smaller teeth along the mesal edge in a series that extends from the proxi- 

 mal end only to the middle, leaving the distal acuminate half smooth. Maxillae 

 II are also unsymmetrically developed, the right one being much larger; it 

 presents two arms meeting at an acute angle anteriorly; the inner arm extends 

 proximad along the mesal side of maxillae II, the base of which it nearly attains, 

 and bears a series of fifteen or more teeth; the anterior arm is shorter and ex- 

 tends down the outer side of the second maxilla. The much smaller left maxilla 

 II is also bent into an angle into which the left maxilla I extends; the inner arm 

 is short, extending but slightly down the mesal side of the first maxilla, and bears 

 seven teeth; the outer arm is very much smaller. Each maxilla III is similarly 

 bent into an angle fitting about the anterior end of the corresponding maxilla 

 II; the inner arm is also the longer and bears about five teeth. The right 

 plate the larger. Maxillae IV are likewise unequal, the right plate being the 

 larger. The right plate bears three slender, acute teeth, and a fourth, the most 

 anterior, blunter one. The left plate presents above a single slender, bifid tooth 

 and below a rounded prominence bearing a minute acute point. The fifth 

 maxillae are reduced to simple hooks, each hook being long, slender, and evenly 

 curved, and arising from a heavier basal piece. (Plate 61, fig. 2) . The mandibles 

 are black in color Uke the maxillae. Each one is a short, strongly clavate piece, 

 narrowing caudad, and in contact with the other plate anteriorly; anteriorly 

 the inner edges diverge from the point of contact and form an acute reentrant 

 angle; the anterior end of each is truncate. (Plate 61, fig. 3). 



Locality. Easter Island. Shore. 20 December, 1904. One specimen. 



