238 TflE GEXESTS OF SPECIES. [Cuap. 



posed to circulate freely about the organism (which is 

 made up of tliem), and to be derived from all the parts of 

 all the organs of the less remote ancestors of each such 

 orijanism during all the states and sta^^es of such several 

 ancestors' existence ; and therefore of the several states of 

 each of such ancestors' organs. It is further supposed that 

 such a complete collection of gemmules is aggregated in 

 each ovum and spermatozoon in most animals, and in each 

 part capable of reproducing by gemmation (budding) in 

 the lowest animals and in idants. 



In many of such lower organisms, therefore, such a con- 

 geries of ancestral gemmules must exist in every part of 

 their bodies, since in them every part is capable of repro- 

 ducing by gemmation. Mr. Darwin must evidently admit 

 this, since he says : " It has often been said by naturalists 

 that each cell of a plant has the actual or potential capacity 

 of reproducing the whole plant; but it has this power only 

 in virtue of containing gemmules derived from every iiart!' ^ 



Moreover, these gemmules are supposed to tend to 

 aggregate themselves, and to reproduce in certain definite 

 relations to other gemmules. Thus, when the foot of an 

 eft is cut off, its reproduction is exi)lained by IMr. Darwin 

 as resulting fr(jm the aggregation of those floating gemmules 

 which come next in order to those of the cut surface, and 

 the successive aggregations of the other kinds of gemmules 

 which come after in regular order. Also, the most ordinary 

 processes of repair are similarly accounted for, and the 

 successive development of similar parts and organs in 

 creatures in which such complex evolutions occur is ex- 

 ])lained in the same way, by the independent action of 

 sei)arate gemmules. 



^ "Animals and Plants under Domestication/' vol. ii. i». 403. 



