POLLINA TION. 



293 



Fig. 98. Crossed tomato. 



order to multiply the chances of success. If flowers of differ- 

 ent ages are emasculated, however, the bag will have to be 

 removed several times to apply the 

 pollen as the stigmas mature, and the 

 chances of success will be lessened, 

 for the flowers should be handled as 

 little as possible. 



Various bags have been devised and 

 recommended for covering the flowers, 

 but none of them yet introduced are 

 equal to the ordinary grocers' manilla 

 bags. The only difficulty is that the 

 smallest size the fourth-pound is too large for many small 

 subjects, but for these the bag can be cut off. A soft string, five 

 or six inches long, is passed through one of the folds of the bag 

 about an inch from the open end, as seen in Fig. 101, and is tied 

 to hold it in place. To make the bag pucker tightly about the 

 stem, it should be moistened just before it is used. 



In some flowers which have long and thick tube-like corollas, 

 and in which the stigma matures quickly, the end of the corolla 

 itself may be tied up. The flowers of squashes and pumpkins 

 are particularly adapted to this treatment, and one is shown in 

 Fig. 102. The flower is tied before it opens. In squash-like 

 plants the flowers usually open early in the morning and the 



flowers are tied up the preceding 

 evening. The corollas soon wilt 

 and bags must be used after the 

 pollen is applied ; and even if the 

 corolla does not wilt and shrivel, 

 insects sometimes eat through it 

 and interfere with the experiment. 

 All imperfect flowers of course 

 Fig. 99. Crossed and uncrossed Q eed no emasculation, but they 

 gooseberries. must be tied up while yet in the 



bud to protect them from pollen. 



As soon as the stigma matures which will vary from one 

 to six or seven days, according to the species the pollen must be 



