1912] Setchell: Studies in Nicotiana 



Section I. Tabacum G. Don 



Nicotiana Tabacum L. 



Under this section there is usually included only one species, 

 viz., Nicotiana Tabacum L. It seems to include all those species 

 of Nicotiana in which the corolla is of various shades of red or 

 occasionally white (albino?), infundibuliform, with the throat 

 somewhat to much inflated, and with the limb patent. The 

 flowers are in panicled corymbs. Under the single species N. 

 Tabacum is grouped a most varied assemblage of varieties, forms, 

 and suspected hybrids as ever were brought together under one 

 specific name. Comes (1895, 1899, and 1905) has attempted 

 to arrange the various forms under some six varieties and also 

 under various supposed combinations of hybrid origin. The re- 

 sult has been to bring some order out of chaos and to point 

 out certain experimental possibilities. Anastasia (1906) has also 

 concerned himself with an inquiry into the typical varieties of 

 Nicotiana Tabacum. He differs somewhat in his ideas from 

 Comes. Howard and Howard (1910) have attempted to arrange 

 and illustrate the types of Indian tobaccos constant in their char- 

 acters, and Hasselbring (1912) has just discussed the types of 

 N. Tabacum grown in Cuba, showing that they remain true to 

 type when grown also in Michigan. 



In these various papers it is evident that all the variety of 

 plants to be referred under N. Tabacum in its broad and com- 

 prehensive use fall under seeming combinations of a few types. 

 The further question as to the origin of these combinations has, 

 as yet, been merely suggested but not proven. Probably there 

 will be no exact agreement, for a while, as to just what the 

 simplest expressions of the fundamental types are, nor can it 

 be settled except by continued and extended experimentation, 

 if it can ever be settled at all. Comes has selected and described 

 six typical varieties and referred all others as combinations of 

 two or more of these. Anastasia thinks that there are only four. 

 I have tentatively selected five as seemingly fundamental. These 

 three sets thus selected are not coincident for the greater part. 



