SCIENCE IN WHEAT-GROWING. 103 



derived from plants reverting to the parental characteristics, as 

 sometimes happens in imperfectly fixed hybrids. 



When flowering takes place in good weather, fecundation 

 goes on regularly, and the chances increase of obtaining a good 

 crop. These chances, on the contrary, diminish when the ear- 

 ing occurs in a rainy time. Probably water gets within the 

 involucre, and the wet pistils imperfectly retain the pollen 

 grains, or their germination is irregular, the pollinic branch not 

 reaching the micropyle, and the ovules not being fecundated; 

 and the ears bear many sterile flowers in which the corn is not 

 formed. 



The production of the corn, of the seed which assures the 

 perpetuity of the species, is the ultimate end of the herbaceous 

 plant ; it is essential that the reserve stores necessary for its de- 

 velopment be accumulated around the embryo inclosed in this 

 seed, and that it find everything near by: the starch which it 

 will liquefy and then transform into cellulose ; the gluten, the ni- 

 trogenized matter, with which it will form the protoplasm of its 

 cells. These reserves must be abundant, so that a part of them 

 may be burned, producing by their slow combustion the heat 

 which favors these transformations. The whole life of the herba- 

 ceous plant tends toward this end of accumulating in the seeds 

 the principles elaborated during its short existence ; and it is pre- 

 cisely this accumulation in the seed of the gluten and the starch, 

 both excellent food-stuffs, for which men have cultivated wheat 

 from the most remote antiquity ; or, if they live in different cli- 

 mates from ours, sow other corn plants rice in the extreme 

 East, maize in America in order to find in their seeds the associa- 

 tion of nitrogenized matter and starch which gives the grain 

 so pronounced an alimentary value that it forms an essential 

 part of the food of a large proportion of the inhabitants of the 

 globe. 



It is easy to follow the migration of the nitrogenized matter, 

 phosphorus, and potash from the lower to the upper leaves, and 

 from these to the end of the stem and the seed. The transporta- 

 tion of these principles has been studied for more than thirty 

 years by a distinguished agronomist, Isidore Pierre, professor in 

 the Faculty of Sciences at Caen. We are less well informed con- 

 cerning the formation of starch. It can not be seen accumulat- 

 ing in the leaves of wheat as in those of a large number of other 

 species, nor are reserves of saccharine matters found in these 

 leaves. The formation of starch is very late, as it does not take 

 place till during the last stage of vegetation. It thus happens 

 that the quantities of starch contained in the grain vary greatly 

 from one year to another. 



The phenomenon of transportation and migration of nitroge- 



