OBSERVATIONS ON A FLAGELLATP] OF OERCOMONAS. 247 



movements of the blood inhabiting Try panoplasma. 

 Indeed, this flagellate in many respects occupies a position 

 intermediate between the genus Bodo and Try pano- 

 plasma. 



The nucleus is clearly visible in the living animal. There 

 is a distinct membrane, and at the centre of the nucleus is a 

 large karyosome. The nuclear membrane is drawn out at 

 one pole towards the insertion of the two flugella, and occa- 

 sionally a clear line may be detected connecting the apex of 



Text-fig. 4. 



Division-stage of free-swiniming form. 



the nucleus with the base of the two flagella. The details of 

 these structures are much more evident in the fixed and 

 stained films. The protoplasm of the body contains food 

 and other vacuoles, but contractile vacuole is not present. 

 Sometimes the nucleus is surrounded with refractile granules, 

 having the same greenish line and refraction as the karyo- 

 some within the nucleus. These may be present in sufficient 

 numbers as to completely obscure the nucleus. Similar 

 granules occur in the protoplasm of encysted forms (fig. 6). 

 These granules stain deeply, and are possibly of a chromatin 

 nature. 



In the hanging-drop preparations especially this organism 



