6i4 Memoirs of the Indian Museum. [Voiy. V 



the foot does not differ from those in front. In the 5th foot there is a marked change. 

 The ventral cirrus is much shorter and stouter, and the bifid setae are replaced by 

 capillaries. The upper capillary setae lie above and behind the posterior lobe, 

 and now show a narrow wing (fig. 14.H). They are accompanied by a single brush 

 seta (fig. 14Q), which has an expanded oblique tip, with about 13 coarse teeth and 

 two external slender teeth, the latter differing very little in length from the others- 

 The ventral capillary setae (fig. 14J) are shorter than the dorsal, and have no wings. 

 They taper suddenly to a very slender tip, and are obliquely striated with smooth 

 edges. 



In the 6th foot the ventral cirrus is reduced to a short stout stump and ventral 

 pad. There are two brush setae in the dorsal division. Three spines lie between the 

 two anterior papillae. They taper rapidly at the distal end to filiform tips, which pierce 

 the skin. In the 7th foot the ventral cirrus is still more rounded, and in the follow- 

 ing segments it consists of a flat glandular pad, large in the anterior segments, but 

 gradually becoming smaller towards the tail. 



In the 10th foot (fig. 14F, and text-fig. 12b) the setigerous lobe forms a rela- 

 tively small part of the foot. The setigerous fillet runs from beneath the anterior 

 ventral papilla round the front of the foot and is connected to the back of the poste- 

 rior lobe. There are four stout spines in the ventral division, and a bundle of fine 

 spines enters the base of the dorsal cirrus. There are three brush setae. The dorsal 

 capillary setae are long, stout, tapering gradually, with narrow wings, only one of 

 which can usually be seen. The ventral setae are shorter with much flatter blades, 

 without wings, and taper much more rapidly to very slender tips. In the 15th 

 foot there are 8 brush setae, in the 20th foot 10. 



In the 15th foot the lower anterior papilla has disappeared (text-fig. 12c), and the 

 fillet is attached to the ventral side of the upper, anterior papilla. In the 28th foot a 

 stout hook appears in the ventral part of the foot, below the setae.- The tip (fig. 14N) 

 is bifid, and the lower tooth, which is slightly bent, is stouter and longer than the 

 upper one. The tip is guarded by two delicate flexible wings. In the 40th foot 

 there are 18 brush setae and 4 or 5 capillary setae in the dorsal division. There are 

 two ventral hooks, the lower one emerging far down on the ventral side of the seti- 

 gerous lobe. 



In the 70th foot (text-fig. 12a 1 ) the branchia and ventral pad are greatly reduced 

 in size. The posterior lobe is still conspicuous, but the anterior papilla is not 

 visible in side-view. Of the ventral setae, only two or three project beyond the skin. 

 They have short broad blades, with slender tips. Some of them seem to have been 

 converted into stout spines with filiform tips. Outside the setigerous fillet there is 

 another fold of skin, which completely surrounds the setigerous lobe. One of the 

 stout ventral hooks emerges with the ventral setae within the fillet, the other is more 

 ventral in position and emerges outside the fillet. There are more brush setae than 

 capillary setae in the dorsal group. 



In the 100th foot the posterior lobe is greatly reduced, and the anterior papilla 

 has disappeared. The setae form a single series, arched round the posterior lobe. 



