10 Records of the Indian Mil sen in. [Vol. XIV, 



have fallen out ; in some segments I cannot discover any setae, and in 

 one bundle I saw only one, though succeeding segments had four or five. 

 The identification is however by no means above doubt. 



C. limnaei is a European species which is parasitic on and in fresh- 

 water Gastropods, or is occasionally free-hving. It has not hitherto, I 

 think, been recorded as living in sponges. 



Chaetogaster bengalensis, Annandale. 



Sindll canal and flooded rice-fields near Than-taung on W. Side of Inle Lake, 

 Southern Shan States ; in Ephydatia fiuvintilis. 28th February, 1917. N. 

 Annandale. A number of specimens, none sexually mature. (No. W. 114-1.) 



The identification rests on a comparison with the types of the species, 

 kindly sent to me by Dr. Annandale. The species was originally ob- 

 tained by him from water snails in Calcutta (1). I may supplement the 

 original account by a few additional particulars, based on an examination 

 of the present specimens. 



The length of a chain of two individuals in the preserved condition 

 is 1-8 mm. or more ; of the first individual of a chain measured sepa- 

 rately, 1 or 1-2 mm. The diameter at the widest j)art is -35 — 38 mm. 

 The comparatively short length just given does not conflict with Annan- 

 dale's statement that the animal measures at least 10 mm. when fully 

 expanded ; the type specimens are the same length as these. 



iV=10 or 11. 



The setae of segment ii are in length 85/x, 90ji-l, and 104fjt in three 

 different specimens. The main portion of the shaft is straight, the 

 prongs are almost equal in length and thickness as a rule, even to the 

 oil immersion lens ; sometimes the proximal prong appears slightly 

 thicker at the base. The position of the nodulus varies from the middle 

 of the shaft to frankly distal (distal to nodulus : proximal to nodu- 

 lus :: 2 : 3). 



In more posterior segments the setae are shorter, GSf/- — 74f^ in 

 length ; in thickness they are about 1-1 [i. Here again the greater part 

 of the shaft is straight, the distal end being hooked, and the proximal 

 gently curved ; no difference can be regularly made out between the 

 terminal prongs, though sometimes the distal seems to be rather longer 

 and thinner. The nodulus varies in position in the setae of the same 

 bundle, — from the middle of the shaft to distinctly distal ; where the 

 disposition could be minutely examined, the innermost seta of the bundle 

 has the nodulus nearest the middle, and the most external seta has it 

 most distally placed on the shaft (c/. Stephenson, 9a). 



The number of setae in a bundle is, as Annandale has remarked, 

 very large ; I counted 16 (as well as lesser numbers) both in the bundles 

 of segment ii and in those further back (Annandale, 15 — 17). The 

 much-curved line of insertion of the setae of a bundle is very striking. 



The prostomium is practically absent, — it is merely the anterior hp 

 of the mouth ; this is a large circular orifice, ventro-terminal, looking 

 obliquely forwards and downwards. The section of the alimentary canal 

 which succeeds the pharynx, usually called oesophagus, is short but 

 quite distinct. The beginning of the next part of the canal, the swollen 

 crop, is marked by a number of cells, arranged in a fairly broad ring 



