Vol. I, No. 4.] Notes on an Indian Worm. 117 
[N. 8.] 
13. Notes on an Indian Worm of the Genus Cheetogaster—By 
Netson Annanpate, B.A., D.Sc., Deputy Superintendent of the Indian 
Museum. (With one plate. ) 
The fresh-water worms of the genus Chetogaster are held by 
some authorities to constitute a separate family; but Beddard,' whom 
I have followedin drawing up my account of Uh. bengalensis, regards 
them as belonging to the Naidomorpha, a rather obscure group of 
Oligochztes which appears to be well represented in the Calcutta 
tanks. Hitherto the genus, well known in Hurope and record- 
ed from America, does not appear to have been reported from 
within the limits of Asia. The Calcutta species is not un- 
common and I have taken specimens of what may be a second in 
the Botanical Gardens at Sibpur. This merely proves, as I have 
already pointed out to the Society, that a vast field lies open to any 
naturalist who would devote himself to the study of Indian pond 
life. Iam much indebted to my friends Mr. F. F. Laidlaw, of 
Owen’s College, Manchester, and Dr. J. H. Ashworth, of the 
University of Edinburgh, both for the generic identification of 
the worm in the first instance and for references to literature later. 
My thanks are also due to Major A. Alcock for his unfailing 
sympathy and assistance in the work undertaken. 
Description of Cheetogaster bengalensis, sp. nov. 
Prostomium forming a large, sub-circular sucker: another 
smaller sucker at the posterior extremity of the body. Csophagus 
longer than pharynx, with two well-marked dilatations, the poste- 
rior of which shows indications of a second constriction in its 
posterior third when empty. The anterior dilatation is covered 
with large, flat, polygonal cells of a faint yellowish colour. 
There is a sense-organ (otocyst?) in the brain: the remainder 
of the nervous system normal for the genus, the somewhat 
discrete nature of the ventral ganglia, their number in the first 
few segments and the separation of the two ventral nerve 
chords in the same region being characteristic, The first pair 
of nephridia is larger than the others posterior to it. Sete 
arrangedon each side of the ventral surface in bundles of from 
15 to 17. Body colourless and almost transparent. Length vary- 
ing greatly with state of contraction, at least 10 mm. when the 
body is fully expanded. There is a very distinct flattened area on 
the ventral surface between the two bundles of sete. Outward 
appearance somewhat resembling that of an Aolosoma. 
Possibly this worm should be regarded as the type of a new 
genus; butit seems more convenient to regard it for the present 
as a Cheetoguster. 
! A Monograph of the Order Oligochexta, p. 804. Oxford, 1895. 
