CHAPTER XVIII 



THE WEIGHT OF THE EMBRYO 



Any discussion of the proportional weight of the embryo in A difficult 

 albuminous resting seeds must be surrounded by a host of ^" ^^^ ' 

 difficulties. The first question to present itself is concerned 

 with the utility of such a discussion, since, if we cannot bring 

 the subject into some sort of relation with other matters 

 affecting the seed, it would not be worth while following 

 it up. But if this seems feasible, we are at once confronted 

 with other difficult questions. Although not directly con- 

 cerned with exalbuminous seeds, we cannot ignore their close 

 connection with albuminous seeds. We must at the outset 

 select some standpoint for viewing this relationship, and much 

 depends on our answer to the query — Which is the older 

 of the two ? 



I suppose that on biological grounds there can be no doubt The 

 that the albuminous is the primal state ; but one has only to and the 

 watch a germinating seed bravely endeavouring to strike into exalbumin- 

 the soil, whilst its cotyledons still within the seed-case are 

 appropriating the albumen, to decide that the albuminous state 

 is the older condition. We here perceive the transition from 

 an albuminous to an exalbuminous state in actual operation, 

 the chief point of difference being that whilst the change, as 

 generally understood, occurs in the seed before it enters the 

 resting condition, here it takes place in the germinating seed 

 after the resting-state stage is passed. Our plantlet is now 

 doing what is often effected within the seed at an earlier stage 



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