Trabut: Origin of Cultivated Oats 



81 



TWO FORMS OF THE BARBED OAT 



B The type {Avena harhata). It has given rise 

 to a number of cultivated forms which seem 

 especially adapted to dry regions. At the 

 right (S) is one of these, A.strigosa, which 

 has hitherto been grouped with A.sativa, 

 but is merely a glabrous form of A. harhata, 

 which has lost the fragility of articulations 

 which characterize the latter. (Figure 18). 



the Algerian oats. The proportion is, 

 in harvests made under good conditions, 

 71% of kernels to 29% of chaff. But 

 the experiments of Captain Bosnot, at 

 the Horse Breeding Station at Tiaret, 

 have shown that the Algerian oat has a 

 coefficient of digestibility a little lower: 

 thus with Houdan oats, 62 grams per 

 kilo escaped digestion and with Algerian 

 oats, 70 grams, — although the White 

 Canada oat, in the same trials, has 75 

 grams not digested. Histological ex- 

 amination of the lemmae does not reveal 

 any difference in thickness or consis- 

 tency from those which are observed 

 in A. sativa. 



c) Selection by density quickly gives 

 a practical restilt, perhaps still more 

 evident in this species than in the 

 ordinary oat. 



d) The Algerian oat is of bright color, 

 but there are also black races, derived 

 from the black forms of calvescens and 

 segetalis which are easily found at 

 harvest time. Avena sterilis segetalis }. 

 nigra (fig. l6) is such a race. 



e) I have succeeded in fixing by 

 selection a race of this oat having only 

 a single awn, on the first flower, the 

 awn on the second flower not developing. 



DIFFERENCE IN DISTRIBUTION. 



Avena fatua has a very different dis- 

 tribution from that of A. sterilis; this 

 species is found on our high plains, the 

 steppes or on the slightly humid Oranian 

 and Tunisian littoral. Like .4. sterilis, 

 A. fatua presents numerous transition 

 forms toward the cultivated type, — 

 A. sativa. 



