80 DISCOVERY CH. 



on the anthers at their tops. This pollen is the fertilising 

 element of the plant, and without it no fruit can be 

 formed. It is carried to the sticky stigmas of other 

 apple blossoms by wind or insects, and then starts 

 changes which result in fruit and seed. The anthers 

 are, in fact, the male organs of flowering plants, and the 

 dust they shed is the quickening influence by which a 

 new generation is produced. In some plants such, for 

 example, as the date-palm, mulberry-tree, and willow, 

 the male and female organs are borne on different trees, 

 but in most cases the flower contains both stamens 

 bearing the pollen on their anthers, and stigmas to which 

 the pollen adheres. 



No plant can ripen its fruit unless pollen is supplied 

 to the female organs. The pollen may come from the 

 male organs of the same flower, be borne by wind or 

 insects from another flower of the same species, or be 

 supplied artificially, but in any case it is essential to 

 fertilisation. This was suspected long before anyone 

 made the crucial experiment of isolating a female plant 

 from the pollen of the male in order to test whether 

 fruit bearing the seeds of another generation would 

 then be produced. 



Prof. L. C. Miall describes, in his Early Naturalists, 

 the conclusive observations and experiments by which 

 the doctrine of the sexuality of plants was established 

 by Prof. R. J. Camerarius, professor of botany at 

 Tubingen, toward the end of the seventeenth century. 

 Experiments were first made with the Annual Mercury, 

 in which the sexes are usually represented by different 

 plants, one of which carries the fertilising element 

 while the other bears the fruit and seeds. Two female 

 plants, when isolated, were found to produce only 

 abortive or unfertile seeds ; and, in like manner, when 



