MISSISSIPPI EXPERIMENT STATION. 15 



hybrid showed an intermediate structure with a leaning toward the 

 pistillate parent. The epidermal cells both on the inner and outer 

 side of the corolla tube, are palisade-like in form and arrangement, in 

 each of the three species, but they are sHghtly different in the two 

 parent species being more narrow and somewhat longer in N. Tabacum. 

 In the hybrid they are similar to the ones in the pistillate parent. 



Ovary: The ovary of N. Tabactim is considerably thicker than 

 the ovary of N. sylvestris (figs. 19 and 21), while the ovary of the hybrid, 

 with the exception of being shghtly larger, is very sirmlar to that of 

 N. sylvestris. In N. sylvestris, the thickness of the ovary waU is about 

 90ti, and the partition dividing the two cells has about the same thick- 

 ness; in N. Tabacum, the ovary waU is 105^ thick and the partition 

 150m; in the hybrid the wall is about 105^ thick, and the partition 130m. 

 The form of the placenta varies greatly in sections cut in different parts 

 of the ovary. 



In the following tables the main morphological and histological 

 characters of parents and hybrid are brought together, in order that 

 they may be compared easily. The ratio of inheritance of individual 

 characters, also the sum total of characters, is expressed in per cent. 

 The only characters listed are those which differed in the two parents. 



