24 MAINE AGRICULTURAL EXPERIMENT STATION. 



tion to the personal characters of the progeny. What the pro- 

 geny shall be like is determined by the constitution of the gerir; 

 cells of the parents. When by a proper system of selective 

 breeding the point is reached where these germ cells are pure 

 with reference to a particular character, or degree of a charac- 

 ter, then that character will unfailingly appear in the offspring, 

 in the degree of perfection in which it is represented in the 

 germ cells. This is the highest goal of the practical breeder. 

 But in a sexually reproducing organism, like the domestic fowl 

 or cattle, purity of the germ cells with respect to the determin- 

 ers of any character is only to be obtained, in the hands of h 

 practical breeder without special scientific training, by the 

 practice of inbreeding. 



It should not be understood that indiscriminate inbreeding 

 without definite purpose or reason is advised, or advocated as 

 a panacea for all the difficulties which beset the breeder's path. 

 All successful breeding is the working out of carefully made 

 plans. In those plans inbreeding has a place. 



WORK WITH PLANTS. 



Beans. 



The experience of the past two years has shown that it is 

 impossible to grow several varieties of beans in adjoining plots 

 without the varieties mixing. The general impression has pre- 

 vailed that the bean flower was so constructed as practically to 

 ensure self-fertilization and to prevent cross fertilization by 

 insects. The pistil and stamens are entirely enveloped in a 

 sheath or tube-like structure. Generally the pollen will have 

 lipened and the ovule will have been fertilized before the bud 

 fully opens. Without the intervention of insects, self-fertiliza- 

 tion would always take place in the bean blossoms. 



Last year humble bees were observed working among the 

 blossoms of the bean plants in the Station's variety tests. 

 Humble bees were seen to light on the lower petals of blossoms, 

 which were borne down by the weight of the bee, and served 

 as levers, throwing the stigma and antlers out of the sheath 

 into full view. The bee brushed its body against the exposed 

 stigma and antlers and then flew to other blossoms, again alight- 

 ing on the lower petals and repeating the operation described 

 above. Hence, it seems justifiable to conclude that the humble 

 bee may be an agent in the crossing of beans. 



