THE FOUNDERS OF THE ART OF PLANT BREEDING 
FRED C. WERKENTHIN 
The paper by Prof. Werkenthin on History of Plant Breeding was 
one of the assigned topics in the course givgn at Iowa State College 
on the History of Botany. The subject matter is so admirably treated 
that' it has seemed wise to publish this as a posthumous paper. It was 
the last paper prepared by him, finished only a few weeks before he 
was taken sick. — L. H. Pammel. 
Since there is a close relation between the mode of reproduction 
and the method of breeding a plant, a knowledge of sexuality 
was, therefore, almost a necessity before it was possible to develop 
the art of breeding. 
Existence of fruit-bearing and sterile trees of the date palm 
was known to the people of Egypt and Mesopotamia in early 
times and records of artificial pollination as early as 700 B.C 
have been found. Kazwini, the Arabic writer on natural history, 
says of the date, “It is created out of the same substances as 
Adam, and is the only tree that is artificially fertilized. The 
seeds of the date produce about half and half, male and female 
trees.” Kazwini, who died about 682 A.D., says plainly in his 
book, “Of the marvels of nature, and of the singularities of 
creating things,” “the date has a striking resemblance to man, 
through the beauty of its erect and slender figure, its division into 
two distinct sexes and the property, which is peculiar to it, of 
being fecundated by 1a sort of union.” 
BEGINNING OF A NEW ERA 
On the 25th of August, 1694, i n his laboratory in the University 
of Tubingen, in South Germany, Rudolph Jacob Camerer, Pro- 
fessor of Natural Philosophy, better known to science under his 
latinized name of Camerarius, finished the writing of an ex- 
tremely long letter to his friend, Professor Michael Bernhard 
Valentin, of the University of Giessen. This letter, which fills 
some fifty printed pages, is entitled “De Sexu Plantarum Epis- 
tola” (Letter concerning the sex of plants). 
Camerarius was the first botanist to discover by actual ex- 
periments that the pollen is indispensable for fertilization in 
flowers, and that the pollen-producing flowers or plants are there- 
fore male, and the seed bearing ones female in nature. Camera- 
