4 BREEDING CROP PLANTS 



"In the vegetable kingdom there is accomplished no reproduction 

 by seeds, that most perfect gift of nature, and the usual means of 

 perpetuating the species, unless the previously appearing apices of the 

 flower have already prepared the plant therefor. It appears reasonable 

 to attribute to these anthers a nobler name and the office of male sexual 

 organs." 



Further Proof of Plant Sexuality. The work of Camerarius 

 was confirmed by several men. Thomas Fairchild, in 1719, 

 produced a new variety of pinks by an artificial crossing; of two 



FIG. 2. Male and female flowers of date palm about two times natural size. 

 (Photograph taken by Swingle in Sahara Desert, 1X99.) 



varieties; and Bradley, two years earlier, found emasculated 

 tulips set no seed. Miller, 1731, noted insects pollinating emas- 

 culated tulips after first visiting untreated tulip flowers. Gover- 

 nor Logan of Pennsylvania, in 1739, experimented with maize 

 and observed that detasseled plants set no seed when isolated 

 from untreated plants. He also removed the silks and found 

 such treated plants were incapable of setting seed. Gleditsch 



