632 Memoirs of the Indian Museum. . [Voiy. V, 



sion shows little change, except that the posterior lobe is rather larger and wider. 

 In some specimens, however, this lobe is narrower and longer than that shown in 

 fig. i8iy. The succeeding feet undergo little change, except that the various lobes 

 gradually become shorter, and the dorsal division relatively increases in size, till at 

 the 90th foot (fig. 1 8m) it slightly exceeds the ventral division. 



The ventral compound setae are of the usual type (fig. i8p, i8q). The end of 

 the shaft is swollen, and the terminal piece is long and slender, with very minute 

 serrations. The dorsal setae (fig. i8n) are of the shape characteristic for the genus 

 Glycinde, having a curved tip with a long slender curved spine on the crest. In none 

 of the feet do they pierce the skin. 



This species is characterised (1) by the small number of rings composing the 

 head ; (2) by the structure of the proboscis, and especially by the small number of 

 dorsal jaws ; (3) by the structure of the feet. 



G. oligodon seems to be most closely related to the G. armigera described by 

 Moore (1911, p. 307), from California, in rather deep water. It differs in the shape 

 of the paragnaths, the smaller number of dorsal jaws, the smaller number of rings 

 composing the head, and in the shape of the foot-lobes. 



Habitat. — Numerous individuals of this species were taken at 12 stations in the 

 Chilka I^ake. With one exception these stations were in the south-western half of 

 the lake. The remaining station was in the outer channel, and was worked during 

 September, when the water was quite fresh. At the other stations, 9 of which were 

 worked in the salt-water season, and 2 in the freshwater season, the specific gravity 

 of the water varied from rooi-j/011. The species was usually taken on a muddy 

 bottom, at some distance from the shore. 



Family ARICIIDAE. 



Scoloplos marsupialis, sp. nov. 



(Plate XXVII, figs. 19A-G, and text-figs. 18a, b.) 



Only a single specimen of this species was obtained, in the Chilka L,ake, but fortu- 

 nately it is complete. It is a male, and the body cavity is full of nearly ripe sperma- 

 tozoa. The body is wide and flattened in front, attaining its greatest width at the 

 13th setigerous segment. It is 50 mm. long, and is composed of 210 segments. The 

 ventral surface is flattened in front for a short distance, but soon becomes markedly 

 convex, and is traversed by a median groove which commences in the 15th segment, 

 and runs to the posterior end. The dorsal surface is convex up to the 5th setigerous 

 segment, and then becomes flat, but the crowding of the parapodia on the dorso- 

 lateral borders makes it appear concave. In the anterior region there is a transverse 

 ridge running round the middle of each segment, dorsally and ventrally. In the 

 middle and posterior regions, each segment is biannulate. The prostomium (fig. 19A) 

 is composed of two rings. The anterior ring is a slender cone, separated by a groove 

 from the posterior ring, which is much wider. The mouth is at the anterior end 

 of the buccal segment, and has two lateral semicircular lips, with a longitudinal 



