4:6 THE PLANT. 



effect a separation of the nitrogenous constituents, the 

 albumen forsaking the leaves and lodging in the seed. 



In the young shoots, buds, and generally in all 

 parts in which the production of cells is most actively 

 carried on, the sulphureous and nitrogenous constitu- 

 ents (albumen) accumulate, and thus the younger leaves 

 are always richer in these substances than the older. 

 The leaves nearest the ground (sand-leaves) give a 

 milder, the upper leaves a stronger tobacco. In those 

 varieties which are not particularly rich in nicotine and 

 albumen, the sand-leaves are of much less value than 

 the upper leaves. A mild tobacco always means a 

 tobacco poor in narcotic constituents. 



The course pursued by the European tobacco plant- 

 er, who lays a superabundance of animal manure upon 

 his fields, is the exact reverse of that adopted by the 

 American planter, who cultivates his plants upon a 

 field that has never been manured. The one seeks to 

 reduce or dilute the narcotic, sulphureous, and nitro- 

 genous constituents of the leaves ; the other to concen- 

 trate them. Accordingly, the American planter breaks 

 the lower leaves in their full vigour, when the plant 

 has attained to half-growth ; the European planter at- 

 taches the greatest value to the fully-developed upper 

 leaves. 



As the tobacco plant, like all annuals, only^ yields 

 up its whole store of organisable matter at the ripening 

 of the seeds, the stem does not die after the loss of the 

 leaves ; but the materials still remaining in it and in 

 the roots cause the stem to send forth fresh shoots, and 

 frequently even leaves, though small-sized ones. In the 

 "West Indies, Maryland, and Virginia, before the gather- 

 ing of the leaves, the stems are notched immediately 

 above the ground, so that they lean over without being 

 severed from the root. In warm weather, the water in 

 the leaves evaporates, and a motion of the sap ensues 

 from the stems and roots towards the leaves, in which 

 the sap is thus concentrated as the plant withers. The 

 tobacco planters on the Rhine have found that a supe- 



