1 92 1.] Fauna of the Chilka Lake : Polychaeta. 589 



nereids are smaller than the average immature individual in the collection, though 

 they have the normal number of segments. The two female Heteronereids were taken 

 in January and February, the small immature male in February, and the spent male 

 in November, so that the period of sexual maturity is evidently prolonged. The 

 specific gravity of the water at these four stations varied only from 1 •006-1 "009. 



Habitat. — This species was found at 15 stations, all south of a line drawn from 

 Nalbano to Patsahanipur. Twice it was found in November, and on thirteen occa- 

 sions in January to March. In this part of the lake, however, the season makes 

 little difference in the specific gravity of the water, which ranged at the various sta- 

 tions from i'002-i'0ii. The habitat of this species varies widely. It was often 

 found in sponges, both Spongilla and Laxosuberites. It. also lives under stones on 

 the shore, amongst algae on the rocks, and in sand above and below high-water 

 mark. 



Nereis (Nereis) glandicincta, sp. nov. 



(Plate XXIII, figs. 9A-1,, and text-figs. $a-e.) 



This species was taken at four localities near Calcutta, in brackish lakes or pools. 

 Twenty-six specimens are available, most of them approaching a state of maturity. 



The preserved specimens are pale buff brown. Running transversely across the 

 dorsal and ventral surface of each segment is a very conspicuous row of dark glands. 

 The glands are continued into the feet, and are especially prominent in the dorsal 

 ligule. They occur to a lesser degree in the median and ventral ligules and the base 

 of the ventral cirrus, but are not found in the dorsal and ventral cirri nor in the 

 setigerous lobes. There is usually a band of glands on the median dorsal area of 

 the peristomium. There is considerable variation in the number of glands in each 

 row. Sometimes they are absent from the median dorsal and ventral areas, and in 

 other specimens they form complete and very thick bands round each segment. The 

 specific name is derived from this character. The dorsal vessel shows very dis- 

 tinctly. The ventral surface is slightly grooved, and the nerve-cord shows as a 

 pale line. 



The type-specimen is 88 mm. long, and comprises 123 setigerous segments. It 

 is a female, full of eggs, but shows no sign of assuming the Heteronereis condition. 



In all the specimens which have the pharynx extruded, the peristomium is large, 

 oval, and greatly inflated. Even when the pharynx is retracted, the peristomium is 

 large, bulging out at the sides and in front of the head. 



The head (fig. ça) is narrow in front, wide behind, where the width exceeds the 

 length. In front are the two short tentacles. The posterior angles are rounded. 

 The eyes vary considerably in size in the different specimens, probably owing to the 

 approaching condition of sexual maturity. They are provided with lenses. The 

 pigmentation of the head also varies. In some specimens there is a conspicuous 

 band on each side of the anterior part, reaching from the base of the tentacles to the 

 front eyes. In others there are only two oval patches of pigment between the 

 posterior pair of eyes. Others have two short lateral and a narrow median band as 



