1921.] Fauna of the Chilka Lake : Polychaeta. 597 



In the 10th foot (fig. iod, and text-fig. 8b) the dorsal cirrus is equal in length 

 to the dorsal ligule, the latter bsing stout and conical. The dorsal setigerous lobe 

 consists of a small papilla lying above the dorsal spine. From the front face of this 

 papilla the fillet runs above and behind it, and is attached below to the median 

 ligule. The setae are all long-tipped homogomphs. The median ligule is stout and 

 rounded. The ventral division is very much as in the ist foot. The ventral ligule is 

 finger-shaped, and the ventral cirrus is small and slender. The long-tipped homo- 

 gomphs and heterogomphs are of the usual type. The falcate heterogomphs (fig. 10G) 

 have short terminal pieces, with smooth tips, and the spinous portion is short. 



The 20th foot is very similar, except that the two lobes of the ventral division 

 are much smaller. In the 30th foot the base of the dorsal ligule has begun to 

 elongate, carrying out the dorsal cirrus with it. The median ligule is also a 

 little longer. In the ventral division the lower of the two lobes is broad and thin, and 

 forms an almost indistinguishable part of the setigerous fillet. The upper lobe 

 is very much reduced. The two upper anterior setae in the ventral group of fal- 

 cate heterogomphs are much stouter than the other setae. 



In the succeeding feet these tendencies are accentuated. The dorsal division of 

 the foot is greatly enlarged (figs. 10K, iof). The papilla in the dorsal setigerous 

 division disappears, but the fillet remains (text-fig. 8c), both edges being fused to the 

 median ligule. In the ventral division the small upper lobe disappears, and the lower 

 one completely fuses with the fillet. 



In the 70th foot (fig. iof) the dorsal division is very large and conical, 

 with many glands. The dorsal and ventral setigerous lobes are represented only by 

 the fillets. In the anterior part of the ventral division two of the falcate hetero- 

 gomphs just above the spine, and one below it are much thicker than the rest. All 

 the feet are very vascular. 



This species has some points of resemblance to N. variegata, Grube {Pavaner eis 

 elegans, Kinberg, 1910, p. 53), Ehlers (1901, p. 112), especially in the colour pattern, 

 but differs in the arrangement of the paragnaths, the length of the dorsal cirri and 

 other foot lobes, etc. In the shape of the feet, especially in the position of the dorsal 

 cirri, it is more closely related to Pseudonereis novae-hollandiae, Kinberg (1910, p. 52), 

 from Port Jackson, Australia, but differs from the latter in having much shorter dor- 

 sal cirri and in the paragnaths of Groups I and V. From N. camiguina, Grube 

 (1878, p. 87), it differs in the shape of the head, length of the tentacular cirri, colour 

 pattern, etc. 



Habitat.— Ten specimens of this species were found, living in burrows or crevices 

 in oyster shells, at Manikpatna in the outer channel of the Chilka Lake. They were 

 taken in September, during the freshwater season, when the water in the outer chan- 

 nel was quite fresh. From the nature of the habitat, it is probable that the species 

 lives there throughout the year. 





