324 



HUTCHINSON'S POPULAR BOTANY 



'P* 



FIG. 393. ABNORMAL FLOWER OF Wistaria, 



With two petaloid stamens (/>.*.) (The keel, wings, and 

 standard have been removed.) 



of what has been before us in this 

 rapid sketch. The process that 

 has been described is the same, in 

 all essential particulars, as that 

 which goes on in the great majority 

 of flowering plants, and it is so 

 simple as to be easily understood. 

 The pollen may be conveyed to 

 the stigma by other than insect 

 agency, and the tubes may pursue 

 a more winding course through 

 the conducting tissue ; but these 

 are details, and the above descrip- 

 tion may be accepted as a fairly 

 representative one. What actu- 

 ally takes place in the ovules when 

 the pollen-tubes have found an 

 entrance will be explained farther 

 on (Chap. XIV.) : it is sufficient 

 here to have directed attention to 



the fact itself. The growth of the tubes may be conveniently demon- 

 strated with the pollen of the cultivated varieties of Caladium, all that 

 is needed being to leave a few grains on a damp microscope slide for five or 

 six hours. 



We have already seen that the beginning of the flower is, like the 

 beginning of the leaf, the bud ; and that a flower-bud and a foliage-bud are 

 indistinguishable in the early stages of growth. The theory of the develop- 

 ment of all parts of the flower from 

 leaves was enunciated by the poet 

 Goethe nearly a century ago : and 

 though the announcement of his 

 discovery was accompanied by a 

 good deal of speculation which 

 subsequent research has shown to 

 be erroneous, his main position had 

 much to recommend it. nor does it 

 lack defenders even at the present 

 day. Goethe taught that " the 

 elementary floret expands into a 

 leaf upon the stem, contracts to 

 make the calyx, expands again to 

 make the petal, to contract again 

 FIG. 394. ABNORMAL FLOWER OF Begonia, into sexual Organs, and expand for 

 With sepals developed a? green foliage leaves. the last time illtO fruit." 



