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claimed for the cells of every plant or animal; they are 

 all descended without break from the earliest dawn of 

 life. An ovum is but a cell of the plant, within which it 

 is formed. It is a highly complex thing, and possesses 

 hidden within it all the characters of the plant. If it 

 could grow it would develop into a plant practically identi- 

 cal with the one from which it was derived, just as is the 

 case when we raise plants from slips or tubers. If, instead 

 of taking a slip of a Kose, we were able to take one of its 

 cells and induce it to grow, a new exactly similar Eose 

 would be produced. This is the regular course with fungi ; 

 they release single cells, which we call spores, and these 

 reproduce beings just like the ones from which they fell. 

 This reproduction of similar forms is called heredity. 



We speak of plant or animal as inheriting its qualities, 

 and think it strange that one cell can carry so many 

 powers. We should all be in a state of marvellous^ con- 

 fusion if it did not. Did no disturbance take place, beings 

 would be the exact counterpart of their parents; but they 

 are never quite that. There is always a tendency to vary, 

 and to account for this tendency is one of those problems 

 that naturalists have not yet come to an agreement upon. 

 It was once thought that if a being became modified by a 

 circumstance of its life, as, for instance, if a man gained 

 great muscular development of his arm by constant use, 

 or a plant formed succulent leaves through the presence of 

 salt, that there would be a ten dency to transmit that power ; 

 but the weight of evidence is against it. If in the savage 

 state some men had great advantage by accidentally 

 possessing strong arms, there might be a survival of strong- 

 armed men and an extermination of weak-armed brothers ; 

 then the tribe would tend to a marked feature of strong 

 arms. The same way with fleshy leaves; if such a con- 

 dition gave a life or death advantage, those plants with 

 a tendency to fleshy foliage would survive in the struggle 

 for existence, while the thinner leaved forms would be 

 crowded out. What we want to discover is the cause of 

 variations: the result of it is evolution. As already 

 stated, an ovum is to us aji infinitely complex thing, and 

 only if it rigidly corresponds in structure to the ovum from 

 which its parent was formed, will it produce a being of 

 exact likeness. An infinitely minute difference in the 

 result and a variation will appear. Probably every seed- 

 ling that grows is a variation in some detail ; it only 

 requires suitable conditions to establish itself, and pos- 

 sibly eventually produce a new species. 



