POLYCH^ETA. BENHAM. 233 



In the 53rd foot, the supra-acicular chsetse are (a) 2 very 

 long, and (b) 4 medium capilliforms. Sub-acicular 5 short 

 capilliforms and 2 acicular chsetse. 



53rd supra-acicular (a) 2 very long, and (b) 4 medium 

 capill. Sub-acic. 5 short capill. and two acicular chsetse. 



The pharynx is long, narrow, cylindrical, extending to the 

 19th segment. 



The lower jaw pieces are short and broad, with a large 

 biting region, which in its outer h?lf is transverse, and on 

 its inner half obliquely inclined backwards. The area of 

 union of the right and left pieces is about one-third of the 

 total length. 



The jaws are dead black, the supports are very slender 

 rods, longer than the whole series of upper jawlets. 



The upper series (PI. xliv., fig. 113) consists of five pieces 

 on each side : the basal pair (I.) are unlike ; the left one 

 has an anterior long claw-like fang, the internal margin of 

 the base is straight, and bears 12-13 short sharp denticulations. 



The right piece (I.) has no claw ; it is a transversely dis- 

 posed plate, with its internal margin produced fore and aft. 

 ; o as to be nearly twice the length of the plate itself, and 

 this edge bears 13 denticulations. 



The next piece (II.) on the right side, extends alongside 

 the basal piece, and under a dissecting lens might readily 

 be overlooked. It is a broad clawed plate, the internal 

 straight margin is produced into 12-13 teeth, the distal ones, 

 small, commence close to the claw, the proximal larger. 

 This internal toothed margin is bent upward, and thus is 

 not readily seen till the plates are moved about. 



The corresponding left plate (II.) has a long stout claw, 

 with 9 denticulations, of which the proximal and the distal 

 are small, and those in the middle stout. 



On the left side, the next (III.) has a large claw with six 

 teeth, the largest in the middle. 



The fourth (IV.) similar, but rather smaller, with six teeth. 

 The fifth (V.) has a single terminal claw, and no subsidiary 

 denticulations. 



On the right side the plates III., IV., and V. are similar, but 

 the third (III.) has seven teeth. 



Remarks. The existence of three tentacles would indicate 

 that the worm belongs to the genus Aglaurides, but the 



