CHAPTER IV 



THE DISCONTINUOUSLY MULTICELLULAR 

 INDIVIDUAL 



This we take as the simplest form of multicellular, if not 

 of living Individual, and is all the product of two fused 

 gametes. Its component cells 1 are not continuous or 

 bound to each other, but are free to live as independent 

 entities or pseudo-Individuals, in general contrast to those 

 of Continuously Multicellular Individuals in whom the cells 

 are bound together in one mass, or in several independent 

 masses, and live for the good of the whole continuous 

 number. The developing Discontinuously Multicellular 

 Individual is composed of many free cells which are probably 

 cycle-stages on the road leading to gamete formation, but 

 the theoretical complete Individual is composed of nothing 

 but terminal stages or gametes. 



The hsemamoeba of malaria will serve as our example. 



The malarial amoeba, whatever the species, is usually 

 described as having two distinct " life-cycles," but it is to be 

 noted that these are in no sense growth-cycles. One " life- 

 cycle " is in man — the " asexual cycle " — and the other in 

 the body of the anopheles mosquito — the " sexual cycle." 

 But the so-called " asexual cycle " is only a cycle in that 

 there is a repetition of immediate environmental conditions, 

 while the " sexual cycle " is not a true one in any sense. The 

 diagram below shows the life-story of the amoeba, and while 

 correctly depicting the phenomena observed, it is nevertheless, 

 as has been said, misleading from the growth-cycle point of 

 view. 



1 A " cell " is the term used to indicate a protoplasmic entity or " pro- 

 toplast " surrounded by distinct walls, and is not strictly applicable to an 

 amoeboid or an unwalled protoplast. But the word is employed here in 

 the widest sense to indicate any protoplast, walled or unwalled. An alter- 

 native heading to the chapter would be " The Discontinuous Polyproto- 

 plastic Individual." 



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