44 THE EVOLUTION OF CONTINUITY 



the spores, however, instead of forming sporocytes assume the sexual 

 or gamete form. These do not reproduce or undergo any change 

 whilst in the intermediate host. If they are taken up by the definite 

 host (mosquito) they become sexually active, conjugation takes place 

 and further development follows. The product of conjugation, the 

 fertilised female, increases in size and forms a cyst. The contents 

 of the cyst divide into several masses, blastophores, from which 

 small thread-like bodies, sporozoites, are formed. These bodies when 

 introduced into a suitable animal — the intermediate host — become 

 sporocytes. This cycle is a sexual one, and the host is therefore the 

 definitive host." 



Now our view is that these asexual and sexual cycles are 

 not true cycles and that reproduction does not take place 

 asexually. In one sense we can recognise an asexual cycle in 

 that there is regular repetition of the phenomena of amoeba — 

 spores — amoeba, and the repetition of entering and leaving 

 corpuscular immediate environment. But what we would 

 call the " true " cycle is the Individual growth-cycle. This 

 begins with gamete-conjugation and ends with gamete- 

 reproduction or restoration. 



The products of the division of the " zygote," or conjugated 

 gametes, are the sporozoites mentioned, and these on entering 

 the blood corpuscles become the first infecting amoebae. And 

 the point we wish to suggest is that no amoebae reproduce 

 themselves in the amoebae resulting from their sporulation. 

 Under the microscope, it is true, there are all the appearances 

 of asexual " reproduction " ; the amoebae resulting from one 

 act of sporulation do appear to be identical with the amoebae 

 which became them ; but it is very probable that this is 

 purely a matter of appearances. Our belief is that each 

 amoeba is cyclically further advanced than that which grew 

 to produce it, and that each amoeba produced is, as it were, 

 a stage in the cycle determining the reproduction of the original 

 conjugating gametes. 



This reproduction is multiple ; more than one gamete of 

 each sex is reproduced, and every amoeba resulting from the 

 initial act of conjugation is the starting-point of a longer or 

 shorter series of amoeba-stages ending in gamete reproduction. 

 According to our hypothesis such series will vary in length 

 according to the situation in line of " descent " of the amoeba 

 originating them. It is the cellular Discontinuity of the 

 Individual which allows every amoeba produced to carry 



