1921.] Fauna of the Chilka Lake : Polychaeta. 637 



the only difference of note is in the shape of the dorsal inferior setae. In both feet 

 the dorsal and ventral lamellae are similar, the dorsal and ventral bundles are verti- 

 cally elongate, the dorsal superior setae are very long, with narrow wings, and the 

 ventral setae are lance- shaped. In the 5th foot the dorsal inferior setae are sharply 

 differentiated from the other setae. They consist of two rows, 11-15 in a row, of modi- 

 fied setae (figs. 20E and 20F). The anterior setae are bilimbate capillaries, short, 

 with very broad wings and rapidly tapering filiform tips. The posterior row consists 

 of rather stout hooks with curved tips. There is not much difference between the 

 setae of the anterior row and the dorsal inferior setae of the 4th foot. Moreover, 

 though the row of dorsal setae is distinctly curved at the lower end (fig. 20B), a 

 similar tendency is observed in the 4th foot. If the 5th foot of P. kempi is compared 

 with that of a typical Polydora (as in fig. 2ib), it is difficult to see how Mesnil's 

 assertion can be maintained. In the typical 5th foot, the dorsal and ventral lamel- 

 lae are absent, and the general disposition of the dorsal and ventral bundle s 

 is more modified. The anterior row of dorsal inferior setae are usually modified 

 as much as, or more than, those of P. kempi. The curvature of the dorsal row 

 of setae of the 5th foot in P.. kempi is much less than in the case of P. anten- 

 nata, as figured by Mesnil (1896, PI. XIV, fig. 22), or Carazzi (1893, Taf. 2, fig. 

 12). 



The 6th foot is very like the 4th, but the dorsal lamella is not quite so large. 

 The setae are as in the 4th foot, except that the posterior row of the ventral divi- 

 sion is composed of very slender thread-like setae. 



There are two pairs of glandular pouches in the 6th and 7th segments, as in 

 P. antennata. 



In the 7th setigerous segment the branchiae appear. They are quite free from 

 the dorsal lamellae, and at first are large. They are only 10-12 pairs of them, and 

 the last few pairs are very small. 



In the 8th foot the ventral crochets appear (fig. 2oj). They are 18-20 in each 

 foot, and they are not accompanied by any capillary setae. On the crest there is a 

 slender tooth so closely applied to the main fang that there is no angle between them. 

 The shaft swells gradually above, and abruptly below, the narrow waist. The longest 

 crochets are in the middle of the row. These crochets greatly resemble those of 

 P. antennata. The dorsal setae are longitudinally striated, slender, and very narrowly 

 winged, the lower ones being short but narrow. The wide form of the 4th foot has 

 disappeared. 



In the 18th foot the dorsal setae, 8 or 9 in number, are very long and slender, 

 wingless, or with indistinct wings. They emerge in a bunch, and no longer form a 

 transverse row. The branchia is reduced to a small papilla, and the lamellae and 

 fillets are small. In this region of the body the feet are insignificant, and project 

 only slightly. In the absence of the posterior region it is impossible to be certain, 

 but the insignificance of the feet in the middle of the body would seem to differen- 

 tiate this species from P. antennata, where, according to Mesnil, the feet of the poste- 

 rior region are very prominent, and the dorsal lamellae and fillets are well developed. 



