64 FIELD CROPS FOR THE COTTON-BELT 



tected by means of a very fine-meshed wire cage to prevent 

 insects from bringing in foreign pollen. The succeeding 

 year the seed from each individual should be planted in 

 an isolated patch in order that it will be fertilized' only 

 with pollen of related progeny. In the following genera- 

 tions select only those plants which come the nearest to 

 the original type and grow them in isolated patches. 

 Usually from four to six years are required to breed the 

 hybrids to a practical state of fixity. 



75. Method of crossing cotton. In crossing cotton 

 it is necessary that the parent plants be selected by the 

 afternoon preceding the day on which the transfer of pol- 

 len is to be made. Late in the afternoon several large 

 flower-buds on each plant should be selected that would 

 open the next morning. The anthers are at once removed 

 from the buds on the plants that are to be used as female 

 parents. This is' best done with a small pair of scissors, 

 pincers, or the blade of a pocket knife (Fig. 15). First care- 

 fully cut away the greater part of every petal, thus expos- 

 ing the anthers which should be removed without bruising 

 the pistil, or female organ of the flower. When the anthers 

 have been removed, carefully pin a small paper bag over 

 the remaining part of the bud to prevent insects from 

 bringing in foreign pollen. 



It is also necessary that the selected flower-buds on the 

 male parent plants be covered with paper bags. This 

 prevents the introduction by insects of pollen from other 

 plants to the flower before the cross is made. If the buds 

 have been properly selected with reference to stage of 

 development, all will reach the suitable stage for crossing 

 at about the same time on the following morning 

 (usually about nine o'clock). This readiness can easily 

 be detected by means of the stickiness of the stigmas on 



