54 THE PLANT. 



95 to 244 days, we find that this would give sufficient 

 time for growing two oat crops, and advancing a third 

 half way to maturity ; and a careful investigation might 

 perhaps reveal that the quantity of sulphureous and 

 nitrogenous constituents produced in the oat-plant is 

 not less than that obtained in turnip-plants from an 

 equal area of ground. 



In the grains of the cereals the quantity of the sul- 

 phureous and nitrogenous constituents is to that of the 

 non-nitrogenous (the quantity of the blood-making sub- 

 stances to the amylum), as 1:4 or 5 ; in the roots of 

 turnips, or in the tubers of potatoes, as 1 : 8 or 10. In 

 the latter, therefore, the quantity of the non-nitrogenous 

 constituents is in proportion to the other constituents 

 much greater. 



"When at a certain temperature the organic process 

 of germination begins in- a grain of wheat, the embryo 

 first sends down a number of rootlets, while the plumule 

 rises upward in the form of a short stem, with two 

 or three complete leaves. Simultaneously with the 

 changes taking place in the embryo, the constituents 

 of the farinaceous body (albumen) become fluid ; the 

 amylum is converted first into a substance resembling 

 gum, then into sugar, while the gluten changes into 

 albumen, and both together form protoplastem (Naege- 

 li's organic food elements), or the food of the cell. The 

 fluidity of the new body enables it to find its way to 

 the places where the formation of cells is going on. 

 The amylum supplies the elements required to form the 

 outer wall of the cell ; the nitrogenous matter consti- 

 tutes a principal ingredient of the cell contents. Simul- 

 taneously with the roots and leaves, small leaf-buds arise 

 upwards on the stem-joint, and small root-buds appear 

 at the basis of the roots. 



In the protoplastem of the wheat-plant the non- 

 nitrogenous matter exceeds the azotised matter as five 

 to one. 



Except water and oxygen, no substance from with- 

 out takes any part in these processes. What the seed 

 loses in carbon by the formation of carbonic acid in 



