Plate XVI. Photographs to illustrate the movement of two 

 polyflagellate protozoa. 



{a) A series of photographs (taken from a cine film) showing 

 the movement of the anterior flagella of Trichomonas termidopsis. 

 All of the anterior flagella w^ere moving together in this case. 

 The prints have been retouched to emphasize the shape of 

 the flagella, which are otherwise only faintly visible. Note 

 that the beat is not unlike that of a cilium — it is unidirectional 

 and shows only one bending wave within its length. 



The undulating membrane runs most of the way around the 

 edge of the animal in these prints, having its origin near the 

 base of the anterior flagella and ending near the projecting 

 tip of the axostyle, which here lies close to the flagellar bases. 

 In most of the prints the waves of movement of the undulating 

 membrane can be seen ; the movement of one wave is indicated 

 by the arrows. 



The interval between the frames is t2 sec. X 170. 



(6) Photograph of a living Trichonympha. The flagella move 

 in waves which pass backwards down the body from the rostrum 

 at the anterior end. Four of these waves are indicated by 

 arrows. x 250. 



