THE FAUNA OF BRACKISH PONDS AT 

 PORT CANNING, LOWER BENGAL. 



Part II. — A new Nematode of the genus Oncholaimus. 

 By Dr. O. von Linstow, Gottingen. 



The Nematode here described was found among filamentous 

 alg^ in a pool of brackish water at Port Canning, which is situated 

 on the Matla estuary in Lower Bengal. 



Fig. I. — Posterior extremity of the male, from the right. 



Oncholaimus indicus, sp. nov. 



Cuticle smooth, without annular rings. At the anterior extrem- 

 ity there is a large oral cavity measuring 0'036 mm. in length and 

 0'0I4 mm. in transverse diameter ; in front of this on the ventral 

 surface there is a conical tooth. The caudal end is thickened and 

 narrows abruptly a short distance behind the anus into a caudal 

 appendage, which measures 0*075 mm. in length and 0*0078 mm. 

 in breadth, and is curved inwards slightly towards the belly and 

 rounded posteriorly. This form of tail is identical in the two sexes. 

 Both in the male and in the female the oesophagus measures one- 

 sixth of the total length of the body. 



The male is 2*71 mm. long and 0*053 mm. broad, the caudal end 

 occupying 1/25*6 of the length of the whole animal. The spicula are 

 equal, being strongly curved ; they measure 0*034 ^^t^- in length. 

 Dorsal to them lies a very short supporting structure. 



The female is 2*71 mm. long and 0*057 nim. broad, and in this 

 sex the caudal end measures one twenty-eighth of the total length. 

 The vulva is situated somewhat posterior to the middle of the 

 body and divides the length anterior to it and that posterior in the 



