i 4 THE PSYCHIC LIFE 



flagella arising in the anterior extremity of the body, 

 directed forwards, and also posterior or caudal fila- 

 ments which are turned toward the rear. This is 

 observed in the genus Trichomonas; the anterior fla- 

 gella serve for purposes of locomotion, perhaps also 

 for the prehension of food; the posterior flagella, on 

 the contrary, are solely organs of loco- 

 motion; they resemble a trailing tail 

 and perform the functions of a rudder. 

 In passing we may point out the 

 great morphological resemblance be- 

 tween the Flagellata and the sperma- 

 tozoa of animals, the antherozoa and 

 -D the zoospores of plants. The organs 



I " of propulsion in these beings are the 



same. 



The Protozoan with its flagellum 

 executes the most varied movements, 

 moving first in one direction, then in 

 another, and in different planes; some- 

 times the animal curves about entirely; 

 but most frequently, when he uses' it 

 as an organ of prehension, he extends 

 \J it its whole length before himself; the 



basilar part remains completely immov- 

 able and rigid, while the free end alone 



Euglenadeses. 



r. c . = contractile re- executes movements destined to drive 

 = r dS of r h e ey p e irt food to the m uth, which is generally 

 ra;o n p e h ; ores;^= h n r u: situated at the base of the flagellum. 

 Ehrenberg gives to the flagellum the 

 name proboscis; its peculiar mobility renders it worthy 

 of this name. The flagellum, like the vibratile cilium, 

 is an expansion of the protoplasm through the envel- 

 oping membrane. M. Certes has observed a Proto- 



