(b) One very broad specimen was discovered. Its 

 greatest breadth was over 7/* and its length about 50//. The 

 well-marked kinetonucleus was 1'78/x from tlie beaked 

 posterior end ; the trophonuelnis. ; , taint purple surrounded 

 by a paler area, was about 3*5/* in breadth and was nearly 

 12'5/i from the kinetonucleus ; the anterior end narrowed 

 rapidly to end in the flagellum nearly 11/* in front of the 

 trophonucleus ; the flagellum itself was nearly 21*5/* long. 

 Three small vacuole-like structures were visible in the 

 anterior portion of the parasite and the whole of the proto- 

 plasm was peppered with large deep blue granules, resem- 

 bling in appearance those of the "mast cells" of human 



(c) An intermediate form between these two types show- 

 ing a number of scattered basophile granules, was seen. 

 Its total length was nearly 3-1/', and greatest breadth 3'5/*. 



In the blood from a Catfish dated 27/5/' 10, the parasite 

 presented a different appearance. Granules were not 

 apparent, but the protoplasm was very deeply stained blue 

 in a somewhat streaky fashion, and the nucleus thereby 

 partly obscured. The kinetonucleus was marked, but a 

 free flagellum as such was not recognisable. A lighter 

 area, now on one side, now on the other of the deeper- 

 stained protoplasm represented the undulating membrane, 

 and this part of the flagellum could just be discerned follow- 

 ing the membrane and crossing the body. At its broadest, 

 the membrane was under 2/* in width. This is the only 

 specimen in which we have been able to recognise this 

 structure. This particular parasite was nearly 53'5/* long 

 and had a diameter of 4'45/*. 



The species under review seems to approach most closely 

 to T. gramtioautn, Laveran and Mesnil, from the eel 

 (Amjitilht riilijuris). lake tins parasite, our species varies 

 much in size, and certain specimens are characterised by 



