ACTION OF ELOWERS. 



85. What it is that causes, a plant to convert some 

 of its buds into flowers, by fashioning the leaves into 

 calyx, corolla, stamens, and pistils* while other buds 

 become branches clothed with ordinary leaves, is be- 

 yond the reach of explanation. There are, however, 

 some facts connected with it which require notice. It 

 is clear that plants begin to fruetify at some determin- 

 ate period, varying in different species. In annuals 

 this occurs in a few weeks or months after germina- 

 tion ; in biennials a longer period is required before 

 this condition is arrived at ; and in shrubs and trees 

 a still greater age must be acquired. The American 

 Aloe will not flower before it is thirty years old, under 



Wolffius and Goethe were quite unknown in England. He says: 

 "The buds of fruit trees which produce blossoms, and those which 

 afford leaves only, in the spring, do not at all differ from each other, 

 in their first stage of organisation, as buds. Each contain the rudi- 

 ment of leaves only, which are subsequently transformed into the 

 component parts of the blossom, and in some species of the fruit also. 

 I have repeatedly ascertained that a blossom of a Pear or Apple tree 

 contains parts which previously existed as the rudiments of five 

 leaves, the points of which subsequently form the five segments of 

 the calyx ; and I have often succeeded in obtaining every gradation 

 of monstrosity of form, from five congregated leaves (that is,, five 

 leaves united circularly upon an imperfect fruit-stalk) to the perfect 

 blossom of the Pear tree. The calyx of the Rose, in some varieties, 

 presents nearly the perfect leaves of the plants and the large and 

 long leaves of the Medlar appear to account for the length of the 

 segments, in the empalement of its blossom. The calyx of the blos- 

 som of the Plum and Peach tree is formed precisely as in the pre- 

 ceding cases, except that the leaves which are transmuted into the 

 calyx separate at the base of the fruit, and become deciduous, instead 

 of passing through and remaining a component part of it" (Trans- 

 actions of the Horticultural Society, vol. ii. p. 864 May 6, 1817.) 



