1^12] Setchell: Studies in Nicotiana 23 



grandiflora or very close to it. What seems in many ways to 



107 



be the var. persica is represented by U. C. B. G. 08. It was 



received under the name of N. viscosa. I have referred to it 



in the present account under A". Langsdorjjii var. grandiflora. 



The corolla tube is provided with a gibbous ring at the summit. 



It is to be suspected as of hybrid origin, the most probable 



parents being N. alata var. grandiflora and N. Langsdorffi. It 



has given plants both yellow and milk-white for the color of 



the upper surface of the limb of the corolla during cultivation 



in the U. C. B. G. 



98 

 N. alata var. grandiflora is represented by U. C. B. G. 05 



_l_ 

 (ef. photograph, reproduced in plate 25), and by U. C. B. G. 06. 



They are both clearly the N. affinis of the gardens, but differ 



slightly from one another. The flowers are large, with the tube 



gradually enlarging up to the limb and with very little trace 



of a gibbous swelling at the very top and that only on the upper 



side. The tube is greenish yellow without and the lower (outer) 



surface slightly purplish. N. alata var. grandiflora has been 



crossed with N. Forgetiana Hemsley (1905, pi. 8006) to produce 



the brilliant red plant of the gardens known as N. Sanderae. 



This hybrid has been grown in the U. C. B. G. under several 



numbers and has exhibited a considerable variety of form and 



color of flower and some variability in habit and fertility. All 



the true N. Sanderae show the influence of the red-flowered 



parent {N. Forgetiana) not only in color, but also in the strongly 



developed gibbous ring in the throat of the corolla just below 



the limb. Other hybrids of N. alata var. grandiflora are known 



in gardens, with flowers varying from white, through pink and 



red to dark purple (bluish in fading). In size and shape, the 



flowers, as well as the habit, vary very little from typical X. 



' 174 



alata var. grandiflora. U. C. B. G. 08 is such a hybrid, giving 

 uniformly dark-red flowered plants in pure-line breeding. 



Nicotiana acuminata (Graham) Hook. 



Our knowledge of Nicotiayia acuminata is based on W. J. 

 Hooker's (1829, pi. 2919) description and plate. In the U. C. 



