THE VEGETABLE KINGDOM. 493 



live retired, and jealous brides conceal their lovers 

 beneath domes of azure and gold. 



The delicate envelopes which attract our regards repre- 

 sent only the ephemeral and perfumed palace in which 

 the mysteries of Hymen are about to be accomplished. 

 But so soon as the golden dust of the stamens is spread 

 iipon the altar, the odorous sources dry up, the veils of 

 the temple fade and wither, and the marvellous edifice 

 soon lies scattered on the ground, whilst the now fruitful 

 mother nourishes her precious offspring. 



All flowers do not exhibit such luxury in these organs. 

 Generally they possess two protecting envelopes, and con- 

 tain at the same time ardent husbands and tender wives. 

 More rarely they present only one sex. In this case the 

 one class, without ornament and without perfume, only 

 contains a few cenobites ; whilst others display all the splen- 

 dour of a harem, the perfumed canopies of which only veil 

 a bevy of sultanas. 



Nature's aim is always clearly defined, and she has pro- 

 fuse resoxu'ces for attaining it. A few grains of pollen, 

 almost invisible, are enough to impregnate a flower, and 

 she pours it out open-handed; ninety-nine hundreths of it 

 may l^e lost. A single spouse — and this is the case with 

 certain of the Cacti — is sometimes siuTounded with five 

 hundred husbands ! ^ 



It is even observed that nature multiplies her resources 



^ When a grain of pollen lias fallen upon the stigma, ;infl is retained by the 

 hairs projecting from the surface, a pollen tube is eraitted, apparently owing to 

 endosmotic action between the fluid exudation from the stigma and the contents 

 of the pollen cell, which latter bursts and sets free the inner lining of the cell 

 in the form of a cylindi-ical tube. This tube passes d(jwn betw'een the cells of 

 the style, lengthening out till it at lust reaches the ovules in the cavity of the 

 ovary. This lengthening was at one time thought to be merely extension, but is 

 now supposed to be due to actual interstitial growth. Having arrived here, the 

 pollen tube enters the foramen at the top of the ovule left by the imperfect clos- 



