American tobacco belongs almost exclusively 

 to that group of this family which comprise 

 the genus Nicotiana. Of this genus there are 

 about 50 separate species, one of which, Nico- 

 tiana Tabacwm, supplies almost all the tobacco 

 of commerce. Plants of this species grow from 



2 feet to 9 feet in height; they have numerous 

 wide-spreading leaves sometimes as much as 



3 feet in length; these leaves may be oval, 

 oblong, pointed, or lanceolate in shape, and 

 are generally of a pale green color when young ; 

 they are arranged alternately in a spiral on 

 the stem; the root is large and fibrous; the 

 stem is erect, round and viscid, branching near 

 the top. The alternate arrangement of the 

 leaves on the stalk, succeeding each other 

 spirally, so that the 9th overhangs the 1st, the 

 10th the 2nd, and so on, is very characteristic. 

 The distance on the stalk between the leaves is 

 about 2 inches. Flowers are in large clusters, 

 with corollas of rose color, or white tinged with 

 pink. The leaves and stalks are covered with 

 soft downy hair. The plant is perennial but 

 crops are usually raised from seed. 



Of this species (N. Tabacum) there are prob- 

 ably more than 100 varieties grown in the U. S. 

 alone. Some of the best known will be described 

 later. 



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