Roberts : Founders of the Art of Breeding 



149 



Pennsylvania, published in Latin (5), 

 an account of his experiments with 

 Indian corn, or maize. In each of the 

 four corners of a plot of ground forty 

 by eighty feet in size, he planted Indian 

 corn. The plants in one corner, being 

 detasseled, produced no seeds. From 

 certain ears, he removed part of the 

 silks, and found that only those grains 

 to which the silks were left attached, 

 became fertilized, and grew to maturity. 

 He also wrapped one ear in cloth before 

 the silks appeared, with the result that 

 no seeds whatever were produced. 



"In 1731, Philip Miller, in the first 

 edition of his "Gardeners' Dictionary" 

 (6) reported his own repetition of Brad- 

 ley's experiment with tulips, as follows: 



"I set twelve tulips by themselves, 

 about six or seven j^ards from any other, 

 and as soon as they blew, I took out the 

 stamina with their summits so very 

 carefully that I scattered none of the 

 male dust; and about two days after- 

 wards I saw bees working on a bed of 

 tulips, where I did not take out the 

 stamina; and when they came out, they 

 were loaded with the Farina or male 

 dust on their bodies and legs ; and I saw 

 them fly into the tulips, where I had 

 taken out the stamina, and, when they 

 came out, I found they had left behind 

 them sufficient to impregnate these 

 flowers, for they bore good ripe seeds 

 which afterward grew." 



Miller also grew male and female 

 plants of spinach apart, and found that 

 the latter bore seeds which contained no 

 embryos. 



In 1751, Gleditsch, Director of the 

 Berlin Botanical Garden, published an 

 account (3) of an experiment in cross- 

 ing a species of palm (Chamaerops 

 kumilis) , of which Sachs says in his His- 

 tory of Botany, "This treatise, in point 

 of its scientific tone and learned handling 

 of the question, is the best that appeared 

 between the time of Camerarius and that 

 of Koelreuter." 



Gleditsch had a pistillate palm in the 

 botanical garden in Berlin, which, 

 although some eighty years old, had 

 never borne fruit. There was a male 

 tree of the same species in a garden in 

 Leipzig. In the spring of 174Q he 



obtained from this tree a quantity of 

 pollen, which arrived in Berlin nine 

 days later, a journey which today re- 

 quires two and one-quarter hours. In 

 consequence of the long journey, most 

 of the pollen had fallen out of the with- 

 ered staminate flowers. Nevertheless 

 he pollinated the female flowers with the 

 loose pollen, and was rewarded by seeing 

 fruit ripen and produce seeds, which 

 germinated in the spring of 1750. 



This sketches briefly all of the import- 

 ant experiments known to have been per- 

 formed in connection with the investi- 

 gation of sex in plants, between the days 

 of Camerarius and Koelreuter. By the 

 middle of the eighth century, therefore, 

 little doubt should have remained in 

 scientiflc minds regarding the existence 

 of sex in plants, or as to the necessity of 

 the pollen as a fertilizing agent. More- 

 over, actual experiments in fertilization, 

 many of them between plants of different 

 species, had been successfully carried out 

 in more than twenty important groups 

 of plants, from many diiferent families. 

 We have also, in Koelreuter's work, a 

 careful study of the characteristics of 

 hybrids, obtained in sixty-five different 

 hybridization experiments, conducted 

 with species from a dozen different 

 genera, belonging to diverse families, 

 together with an accurate comparison 

 of the characters of the hybrid plants of 

 the first generation with those of their 

 parents. 



A scientific foundation was therefore 

 laid at last for the breeding of plants. 

 The value of Koelreuter's experimental 

 work was doubted, however, by influ- 

 ential contemporary critics, although 

 Sagerer (7), whose opinion should have 

 carried weight, said of Koelreuter: 

 "Having several times repeated his 

 experiments I have had occasion to con- 

 vince myself more and more of his exact- 

 itude and of his veracity; I believe then 

 that he merits all confidence." It was 

 the fate, therefore, of Koelreuter as of 

 Camerarius, to remain practically un- 

 known and unheeded by his own genera- 

 tion, and to exert no influence whatever 

 upon the theory and practice of his day. 



Despite, however, the fact that Koel- 

 reuter had demonstrated the pos.dbility 



