268 



JOUENAL OF THE ROYAL HORTICULTURAL SOCIETY. 



August 1910; plates). — The author is well known for his discovery on 

 Mount Hermon of a wild emmer from which our cultivated types of 

 wheat and related cereals seem to have been derived. 



This bulletin calls attention to the similarity in general topography, 

 climate, vegetation, and agricultural and economic possibilities between 

 Palestine and the State of California, and gives a long list of economic 

 plants and of fruit trees which might profitably be introduced from 

 Palestine into California, either to serve as stocks or as useful new 

 varieties. 



He then gives an account of the circumstances which led up to his 

 finding the wild emmer (Triticum dicoccum dicoccoides). The cultiva- 

 tion of some form of wheat began long before the dawn of history, and 

 it was only in the nineteenth century that the question of an original 

 ancestor of our cultivated varieties began to be scientifically considered. 

 Even then, after the abandonment of several untenable theories, the 

 conclusion was come to for a time that while Hordeurn spontaneum 

 was the original wild form of barley, and S scale montanum was the 

 prototype of cultivated rye, the genealogical record of wheat had dis- 

 appeared for ever and that its life history could be written only 

 hypothetically. 



Wheats have been classified as follows: — 



In the section Eutriticum there are three species, Triticum mono- 

 coccMm (einkorn) Trit. polonicum (Polish wheat) and, thirdly, a 

 collective species Triticum sativum. Triticum sativum is divided into 

 three small species : — 



T. dicoccum (emmer), 



T. Spelta (spelt), 



T. tenax (common wheats). 



Of these T. tenax is subdivided into sub-species : 



T. vulgare (wheat), 



T. compactum (short -eared wheat), 



T. turgidum (Poulard wheat), 



T: durum (durum wheat). 



This classification is essentially artificial and the distinction between 

 the groups is very difficult to maintain. The behaviour of crosses and 

 hybrids also nidicates a very close relationship among the so-called 

 species, T. monococcum alone refusing to hybridize with the rest. The 

 others pass so gradually into one another that it seems more than 

 probable that all existing wheats belong really to one species. When 

 we come to the consideration of what the original prototype of our 

 wheat must have been, there are certain characters whose existence we 

 may pre-suppose. Among these is undoubtedly a fragile rachis. All 

 who have studied the question agree that a rigid rachis is an acquired 

 characteristic developed by man, and has a tendency to destroy the 

 plant's natural capacity to disseminate itself. Again, it would be needful 

 that the grain in its wild state should remain fixed in its glumes as a 

 general protection against premature germination, decay, and destruction 

 by enemies, while this is a peculiarity which makes the grain trouble- 



