6o Memoirs of the Indian Museum. [Vol. V, 



considerable part of its length it is closely packed with small oval pellets of mud. 

 The canal is joined to the body-wall by numerous slender muscular strands which 

 are very easily detached. 



The natural colouration is much less conspicuous than in some species of the 

 genus. The body-wall is translucent in life with a pale vinous tinge ; but the mud 

 in the alimentary canal makes it seem much darker , sometimes nearly black. 

 The circum-anal region is dead white, the proboscis cream-coloured, with the free 

 edges and the dendritic outgrowths tinged with brown. There are several opaque 

 longitudinal streaks on the body which simulate muscle- bands. Specimens become 

 opaque in spirit and lose their colour completely. 



Apart from the Gangetic species (which we describe as T. branchiorhynchus) 

 T. dendrorhynchus is most nearly related to T. sabinum, Manchester. L The only pub- 

 lished description of the latter is very incomplete; but, as has already been stated, 

 we have been able to examine the type-specimens. The most important diagnostic 

 character is the fact that the lateral margins of the proboscis are fused, so that the 

 organ is tubular. Comparatively long finger-shaped processes arise from its internal 

 surface and protrude at the opening of the tube. Otherwise, except for its small 

 size and comparatively smooth external surface, the species closely resembles 

 T. dendrorhynchus. 



Fischer's description of T. semoni, 1 which was based on specimens that had 

 lost their proboscis, shows that the internal anatomy is similar in most respects to 

 that of the Chilka species; but Shipley's figure of a living individual 5 proves that 

 a wide difference exists in the structure of the missing organ. Wharton, in the 

 paper cited above, has recently redescribed T . semoni, which is an Indo-Pacific form. 



So far as published figures of the entire animal are concerned, T. dendrorhynchus 

 most closely resembles T. kokotoniense , Fischer/ another form widely distributed in 

 the Indo-Pacific region, but in the latter species the longitudinal muscles are divided 

 into bands and the body- wall is apparently much stouter. 



Specimens from the Chilka L,ake were very sluggish when removed from the 

 mud in which they were taken. The only movements exhibited were quite unrhythmic 

 contractions, both transverse and longitudinal, of the body-wall and proboscis; 

 the latter showed no signs of great extensibility or of readiness to break off, and its 

 movements did not suggest that it was employed in burrowing. 



A female killed in February contained immature ova. 



We found only three specimens of T. dendrorhynchus , all in the southern part of 

 the main area of the Chilka Lake. They were living, probably rather deeply buried, 



1 Proc. Zool. Soc. London, 1905 (I), p. 40, pi. ii, fig. 5. 



2 In Semon's Zool. Forsch. Australien, V, p. 338, fig. 4 (1896). 



3 In Gardiner's Faun. Geogr. Maldives and Laccadives I, p. 129, pi. vi, fig. 4 (1903). 



* See Shipley in Willey's Zool. Res. New Britain and New Guinea, p. 337, pi. xxxiii, fig. 3 

 (1S98-1902). 



