604 APPENDICES. 



to Mitrophanow that they were possibly the cytozoa described by 

 Gaule ; but this idea was dismissed by the fact that they were 

 found in blood to which no salt solution was added. Their size 

 varied from 30 to 40 /* in length and 1 to 1| /^ in width. At first 

 their rapid movements baffled examination, but as the rapidity 

 lessened there was the appearance of a curling movement in the 

 body portion and a swinging movement of the lash. The organism 

 moved in the direction of the lash, the anterior end of the body 

 being more pointed than the posterior, and gradually fining off into 

 the lash. When the body seemed to rest, the lash might be seen to 



Pig. 243.— Obganisms in the Blood oi' Mud-hsh {Hcematomonas colitis), a, First 



variety ; b, second variety ; c, third variety, d, First variety in a state of 



diminished activity, e, The same after treatment with osmic acid. (Mitro- 

 phanow.) 



whip out in all directions. As the movement of the body gradually 

 diminished,' it appeared to have a complicated screw form, the axis 

 of the screw corresponding to the body to which an undulating 

 membrane is fastened spirally. This could be distinguished when 

 the organism was dying, because the body in death contracted, and 

 the membrane then looked like a spiral addition. Thus the 

 organism consisted of a body, a spiral membrane, and a flagellum. 



With higher magnification the organism appeared to consist of a 

 refractive, strongly contractile protoplasmic substance, which, when 

 death occurred, formed a shapeless mass. In the same blood two 

 other forms were observed: one without a membrane, but having 



