192 PRINCIPLES OF GARDENING. [CH, VI. 



vegetables the same sexuality as animals. Subse- 

 quent researches have established the fact beyond 

 the reach of reasonable doubt. 



In favourable seasons, when genial warmth and 

 gentle winds prevail, impregnation is readily affected 

 by the plant's own provision. The pollen is never 

 shed from the anther of the stamen, until the stigma 

 of the pistil is fully developed ; and this soon withers 

 after the contact. The gaping of the stigma when 

 the pollen is about to fall, and at that time only, 

 may be observed in the heart's-ease [Viola tricolor) ; 

 and every morning, on the summit of the stigma of 

 the Jacobean lily [Amaryllis forviosissima), a drop of 

 viscous hquid protrudes, to be re-absorbed as regu- 

 larly at noon, with the pollen shed upon it, until 

 impregnation is completed — the drop then exudes no 

 more. But, as was first observed by Sir J. E. Smith, 

 the process, as it is effected in the berberry [Berheris 

 vulgaris), is the most curious. In the flowers of this 

 shrub the six stamens, spreading moderately, are 

 sheltered under the concave tips of the petals, until 

 some extraneous body, as the feet or tnmk of an in- 

 sect searching for honey, touches the inner part of a 

 filament near the bottom. The irritability of that 

 part is such, that contracting and thrown forward 

 spasmodically, it dashes the anther, full of pollen, 

 against the stigma. 



The above are only a few of the modes by which 



