BEER AND FLOWERS. 471 



qncntlv the iiiiii'iiious lioiicv bee lakes advantau'c of tlic pcrforalions 

 iiiado by earlier visitors of this class to get at the nectar luoiv <iiiickly. 



l)ut it is useless to dwell longer upon these points. Bees are 

 athnirabiy athipted to the collection of nectar and of pollen, and these 

 two products are necessary to them and sullicient for them at any age, 

 so nuich so that one may say, with M. l\'rez, that ''every species of 

 bee without exception would disappear if (lowei's should ceas(» to 

 bloom or if they should cease to produce nectar and j)ollen." 



This fact well (established — that Howcm-s are indispensable to the bee, 

 it is next necessary to see if the bees are in I'elurn of any service to the 

 flowers, and, if so, how nnu;h. The <|uestion has been nuich discussed, 

 and to this chiefly are due the differences of opinion that I will speak 

 of in a few moments. 



r>efore entering the thick of the fray, Jet me explain a few of 

 the fundamental })rinciples governing the fertilization of phanerog- 

 amous idauts. In most of these plants, especially the more common 

 ones, the stamens, or nuile' organs, and the ovules, or fenuile organs, 

 are fouiul in the same flower, which in that case is called a heruuii)hro- 

 dite. On its periphery are found the stamens crowned by the anthers 

 containing the pollen and in the center rests one or more sacs which 

 are united to form the pistil and which inclose a varying number — • 

 always infinitely less than the number of pollen grain — of ovules. 

 For these to become seeds it is necessary that the pollen germinate on 

 the pistil and, by working through it, unite with each ovule. In the 

 plants of which the flowers are unisexual — that is to say, some flowers 

 are male, others female — the process is the same except that in this 

 case it is necessary that the pollen be brought to the pistil of the 

 female flower. 



This is brought about in two ways, by close fertilization and by 

 cross fertilization. In the former the ovules are impregnated l)y the 

 pollen of the flower which contains them, in the latter the fertilization 

 is from pollen of a difl'erent plant. Darwin has shown that cross fer- 

 tilization is much more advantageous to a plant than close, and that 

 the maxinnuu benefit is obtained in the crossing of two varieties of the 

 same species. The advantage is shown in general by a more robust 

 vegetation, an earlier flowering, and the fornuition of more and better 

 seeds. Darwin's demonstrations rest u])on an abundance of exjMU'i- 

 ment and observation, and ai"e. moreover, justified by modern i)ractice 

 extended even into the aninuil kingdom. 



Nothing indicates more clearly the advantages of cross fertiliza- 

 tion than does its great predominance in the vegetable kingdom; it 

 is absolutely necessary in the case of plants with unisexual flowers, 

 and, despite all appearances to the contrary, obtains in many, if not 



