202 PHYSIOLOGICAL BOTANY. 



tion and its peculiar normal functions, so will also the 

 individuals produced by it, and by all those which follow 

 it, and which possess their own separately, i. e. modified 

 according to the stages of their development and their 

 age, the second being directly and constantly grafted upon 

 the first ; the third upon the second, and so on, each one 

 being grafted upon the other. The first individual, the 

 embryo, derives the principles of its existence from without, 

 from water, air, light and heat, but especially from the 

 albuminous body (perisperm), when it is present, which 

 nourishes the embryo, and is thus absorbed ; the second 

 is nourished by the first ; the third by the second and 

 the first, and the fourth by the three others, as well as by 

 the elements previously named; hence it foUows, that 

 when the phytons are perfectly developed, the first re- 

 mains very weak ; the second is somewhat stronger ; the 

 third is still stronger ; and that all the subsequent ones 

 become stronger and stronger, as also more complicated 

 in form, and consequently in functions, until we arrive at 

 the normal leaf, which has attained the highest stage of 

 organization." 



Gaudichaud says, all botanists now know that the em- 

 bryo is a bud, whence it may be readily deduced, that 

 the bud is just the same as the embryo, and must have 

 roots like it. But this is not the case, the embryo is not 

 a bud, nor the bud an embryo. There is an old and 

 every-day observation, which I am accustomed briefly to 

 explain in the following manner : the embryo produced 

 by impregnation propagates the species ; the bud, the 

 individual. A branch with buds, from a Borsdorf apple- 

 tree, when grafted always produces Borsdorf apples, 

 whilst the seed of a Borsdorf apple never does so. Dif- 

 fering in this important property, it may also differ in 

 other respects, hence it does not follow that the bud 

 should have roots like the embryo. Moreover, the leaf is 

 not an individual, it is only such when united with the 

 buds, and these at first contain only cellular tissue, 

 extremely few spiral vessels. Such buds, when united 

 together, form Mirbel's Phyllopliore. 



