58 THE PSYCHIC LIFE 



movement is demonstrable among twelve thousand 

 micro-organisms constituting a colony, it must be in- 

 ferred that their movements are regulated by the 

 action of a diffused nervous system present in the 

 protoplasm. This conclusion is all the more inter- 

 esting from the fact that these Volvox are vegetable 

 micro-organisms. 



In the dioecian Volvox, the female cellules and the 

 male cellules are joined together by themselves in sep- 

 arate colonies. When the time of fecundation arrives, 

 the male cellules or antherozoids scatter and proceed 

 to conjugate with the female cellules. The colony 

 which bears the female cellules also contains neutral 

 cellules which are not designed for fecundation; the 

 latter simply perform a locomotive function; equipped 

 with one eye and two flagella, they are intended to 

 move the great colonial ball: they are the oarsmen of 

 the colony. The Volvox, male, female, and neutral, 

 all seek the light, whether solar or artificial, and settle 

 near the surface of the water. As soon as the female 

 colonies have been fecundated, the oospores change 

 their color: they turn from green to an orange yellow. 

 At this point, the colony is seen to draw away from 

 the light and to disappear from the surface of the 

 water. This change of position is effected by means 

 of the vibratile cilia with which each neutral cell is 

 furnished and which project beyond the gelatinous 

 sphere; now, as no change of color or form is noticed 

 in the neutral cells after fecundation, it may be asked 

 from what cause they flee from the light which they 

 formerly sought. 



Colonies of Proto-organisms formed by the division 

 of a mother cell of which the segments remain united, 

 are not entirely without analogy with a pluricellular 



