240 A TEXT-BOOK OF GRASSES 
265. Origin of wheat—None of the cultivated wheats 
is now found growing spontaneously, that is, as a native 
plant. Various theories have been advanced as to their 
origin. Some botanists have supposed them to be derived 
from wild species now extinct or possibly existing in unex- 
plored regions. Others have thought them to be the 
greatly changed descendants from common wild species 
such as Triticum ovatum Rasp. (4gilops ovata L.). (See 
Fabre, Journ. Roy. Agr. Soc. 15: 167. 1854.) Schulz has 
recently suggested the probable origin of the cultivated 
forms. He considers the cultivated wheats to be culture- 
form groups rather than species, subspecies or races. 
Nomenclatorially he recognizes the following: T. mono- 
coccum, T’. spelta, T. dicoccum, T. vulgare, T. compactum, 
T. turgidum, T. durum, T. polonicum. The first-mentioned, 
T. monococcum, he believes is derived from the wild T. 
egilopoides Bal., and the third, 7’. dicoccum, from the wild 
T. dicoccoides K6rn., recently discovered by Aaronsohn 
in the region of Mount Hermon, Palestine. (See Cook, 
U.S. Dept. Agr. Bur. Pl. Ind. Bull. 274. 1918. Aaronsohn, 
Op. cit. 180: 38. 1910. Verh. Zodl.-bot. Ges. Wien. 59: 485. 
1909. Altneuland Monatschr. Wirtsch. Erschl. Palas- 
tinas 213. 1906. Bull. Soc. Bot. France 56: 237. 1909. 
Schweinfurth, Ber. Deutsch. Bot. Ges. 26a: 309. 1908.) 
The second, 7. spelta, he considers to have been derived 
from an as yet undiscovered wild species. Furthermore he 
thinks that 7’. vulgare and T. compactum were derived from 
T. spelta, and that T. turgidum, T. durum and T. poloni- 
cum were derived from T. dicoccum. (Schulz, Mitt. Natf. 
Ges. Halle 1:14. 1911.) Aaronsohn considers 7. dicoccum 
to be the prototype of true wheat and the former to be 
derived from T’. dicoccoides (U. §, Dept, Agr. Bur. PI. 
Ind, Bull. 180: 41. 1910). 
