PLANT-BREEDING ' 



271 



Fig. 175. — Case of instruments and 

 sacks for crossing plants. 



(153), we emasculate the flowers, i.e., remove the anthers 



(143) before the pollen is mature. Prior to maturity, 



the anthers are generally 



pale in color and nearly 



smooth on the surface, 



with no visible pollen, but 



a little later, the pollen in 



most plants is visible as a 



bright yellow dust adher- 

 ing to the anthers. The 



anthers may be picked off 



with the forceps, or the 



filaments that support them may be clipped off with the 



points of the scissors. They must generally be removed 



before the petals open 

 (142). The latter may 

 be gently opened with the 

 forceps or needle, or they 

 may be carefully removed. 

 A set of useful imple- 

 ments for this work is 

 shown in Fig. 175. 



In the flowers of certain 

 plants, such as the pea, 

 wheat and grape, pollina- 

 tion takes place before the 

 blossom opens, hence in 

 these plants it is necessary 

 to emasculate the flowers 

 very early. 

 442. To prevent undesired pollination, the blossom 



should be inclosed by tying over it a sack of thin cloth 



or paper at the time of removing the anthers. The sack 



Fig. 176. — Emasculated flower in- 

 closed in sack. 



