ON CH^TOBBANOHUS. 83 



On Chaetobranchus, a New Genus of 

 Oligochsetous Chaetopoda. 



By 



Alfred Gibbs Bourne, I>.Sc.l<ond., F.I^.S., C.IIf.Z.S., 

 Fellow of University College, London, and of the Madras University. 



With Plate XII. 



Habitat. — I discovered this very remarkable worm in the 

 mud from a pond (Anglo-Indian 'Hank^^) in Madras town. 

 The mud had been placed in a bottle and allowed to stand, so 

 that the Naids for which I was searching might come to the 

 top. On examination I found projecting from the surface of 

 the mud, among numerous individuals of Nais and Dero, 

 several specimens of this worm. These at once attracted my 

 attention on account of the branchial processes, which could 

 be seen with the naked eye. The mud is of a very finely 

 divided character and is brown in colour, and contains very- 

 little animal and hardly any vegetable life, and very little or- 

 ganic debris. I obtained a large quantity of it, and by 

 the use of muslin sieves secured numerous specimens of 

 Chaetobranchus. 



The worm does not secrete any glutinous material, and so 

 make itself a mud tube ; but, as I have been enabled to ascer- 

 tain by keeping them in a small aquarium nearly filled with 

 the mud, makes for itself long tracks in the mud — ^'burrows," 

 they might be called ; and each worm appears to reside in its 

 own ^'burrow," at times projecting from the surface of the 

 mud into the water, and at other times withdrawing itself com- 

 pletely into its '' burrow.'^ The mud is of such a character 



