78 



The Journal of Heredity 



THE TWO SPECIES CONTRASTED 



Nos. 1, 2, 3, 4, arc the ordinary cultivated oat of temperate regions, Avena 

 saliva. 1. The spikelet. 2. The lower flower with the fragment of the 

 axis which bore the second flower. 3. and 4. The second flower, 

 disarticulated. Nos. 5, 6, 7, 8 are the Algerian oat, a cultivated form 

 of A.sterilis, which can be most easily distinguished by its method 

 of disarticulation, in which the second flower carries away its own 

 axis, as shown in 7 and 8. No. 6 shows the third flower without the 

 second axis (compare with No. 2, showing the same flower in .1 . saliva), 

 while No. 5 shows the whole spikelet of this Algerian oat. (Figure 14.) 



and Sirodot' in their monograph on 

 oats, in connection with the Abruzzi 

 oat, indicate good characters and even 

 propose to separate the Abruzzi oat and 

 the Algerian and Tunisian oat as 

 sections of A . sativa. Haussknecht, who 

 studied the forms of steriHs very con- 

 scientiously, expressed the wish to see 

 a useful race arise some day from this 

 group which is so well adapted to the 

 Mediterranean region; in 1894 in the 

 Mitthcilungen des Thiiringisches 

 Botanisches Vercins (n. f. no. 6, p. 39), 

 he expressed himself thus: "For the 

 countries of Southern Europe, Avena 

 sterilis, improved by cultivation, on 

 account of its larger yield, would ])ro- 

 duce a very desirable forage plant, 

 esi^ecially where our A. sativa will not 

 thrive well." If Haussknecht had had 

 occasion to study the southern oats in 

 the field, he would certainly have de- 

 clared that his wish had for a long time 

 been realized, and that his Avena 



sterilis parallela was nothing more than 

 an escape from cultivation. The exis- 

 tence of a whole scries of forms uniting 

 the most characteristic .4. sterilis with 

 the oat which is cultivated in southern 

 countries, is a strong chain which can- 

 not be neglected, while a study of the 

 morphological and physiological char- 

 acters of the Algerian oat reveals 

 affinities which no longer leave any 

 doubt. 



The section of Avena sativa char- 

 acterized by non-articulate flowers which 

 are separated only by the breaking of 

 the axis, is based on an artificial 

 character. It is because of cultivation 

 that the articulations liave ceased to 

 function. 



The group of .4 . sativa is made up only 

 of the hairless and ankylosed oats of the 

 other sections bifonues and conformcs. 

 Avena sativa has retained all the char- 

 acters of its ancestor, A. fatiia. The 

 second flower still separates easily from 



'L'Avoinc, pp. 181, 301, I'JOl. 



