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 

 e great morphological resemblance be- 

 tween the Flagellata and the sperma- 

 tozoa of animals, the antherozoa and 

 the zoospores of plants. The organs 

 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 



V-' it its whole length before himself; the 



basilar part remains completely immov- 

 Fi e 4- able and rigid, while the free end alone 



Euglenadeses. - . . , . 



executes movements destined to drive 



r. c. contractile re- 

 servoir; * -eye, /. f OO( j to the mouth, which is generally 



disk of the para- J 



myione; ch. - chro- situated at the base of the flagellum. 



matophores; . nu- 

 cleus. 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- 



