SPECIES CROSSES IN THE GENUS NICOTTAKA. 227 



a similar purely Mendelian explanation to that which was 

 subsequently discovered for the sweet peas will not be found 

 to meet the case of Nicotiana. 



\0.— BIBLIOGRAPHY. • 

 De Candolle. Prodromus. Part 13. Paris . . 1852 



O. Comes. Monographie du Genre Nicotiana. 



Naples . . . . . . 1899 



W. 0. Focke. Die Pflanzen-Mischlinge. Berlin . . 1881 

 C. F. von Gsertner. Bastarderzeugung. Stuttgart.. 1849 

 J. G. Kokeuter. Vorlaufige Nachricht. Leipzig 1761-1766 

 J. P. Lotsy. Vorlesungen uber Deszendenztheorien. 



Part II. Jena . . . . . . 1908 



J. M. Macfarlane. In Trans., Roy. Soc, Edin., 



Vol. XXXVII., Part I., No. 14 . . 1892 



G. J. Mendel. Versuche uber Pflanzenhybriden. 



Brunn . . . . . . 1865 



DeVries. Die Mutationstheorie. Bd. II. Leipzig 1903 



n.— DESCRIPTION OF PLATES. 



Plate 18. — Nicotiana tabacum X glauca. Plants grown 

 in open ground and in a pot under glass for comparison. 



Plate 19. — N. tabacum X glauca. Pot plant. Height, 

 24 m. 



Plate 20. — N. acutiflora X alata (hybrid). Height, 28 in. 



Plate 21. — N. paniculata X langsdorfii (A). Height, 11 in. 



Plate 22. — N. rustica X paniculata. Height, 16 in. 



Plate 23. — N. rustica (on left) ; height, 24 in. N. rustica X 

 paniculata (on right) ; height, 27 in. 



Plate 24. — N. langsdorfii, var. B X var. A. Height, 24 in. 



Plate 2-5.— N. langsdorfii, vai. C. X vai. E. Height, 20 in. 



Plate 26. — N. langsdorfii, var. A. X N. alata (hybrid). 

 Height, 22 m. 



Plate 27. — ^N. paniculata. Height, 20| in. 



Plate 28.— N. alata. Height, 28 m. 



Plate 29. — N. tabacum. 



7(1)09 (30) 



