AMERICAN BEE JOURNAL. 



661 



The oaks, walnuts and sycamores are all 

 monoecious. 



In many hermaphrodites, plants with 

 perfect flowers, where each flower bears 

 both stamens and pistils, there is a very 

 curious provision which insures cross- 

 pollination. 



In some plants called dichogaraous, 

 the pollen is ripe, and discharged either 

 before or after the stigma is ripe, or 

 ready to receive it. This is seen in some 

 of our pears, and is a common pecu- 

 liarity among plants. Other hermaph- 

 rodites, known as heterogonous, have 

 two kinds of stamens and two kinds of 

 pistils, one long and the other short. 

 One set of flowers have long pistils and 

 short stamens, and the others short pis- 

 tils and long stamens. In these cases 

 insects transfer the pollen, and cross- 

 pollination is insured. 



In all these cases, we see that nature 

 has fenced against close pollination, or 

 as some one has suggested, nature seems 

 to abhor close pollination. The flowers 

 have so developed in the process of evo- 

 lution, that cross-pollination is enforced, 

 and in the last case we see that insects 

 have controlled in giving trend to the 

 development. The other argument 

 comes from direct experimentation, and 

 proves that many perfect flowers require 

 cross-pollination. Flowers were emas- 

 culated just as they were opening, before 

 the pollen was ripe. That is, the stamens 

 were all removed. When the stigmas 

 were ripe- for the pollen, they were 

 dusted with pollen from other blossoms 

 on the same tree, from those of other 

 trees of the same variety, and from 

 those of trees of other varieties. Other 

 blossoms were covered, and the stigmas 

 dusted exclusively with pollen from their 

 own stamens. 



These experiments gave different re- 

 sults with different fruits, and with dif- 

 ferent varieties of the same fruits. 

 Some varieties are perfectly sterile, and 

 others perfectly pollinated with their 

 own pollen, or that of the same variety 

 of trees, while others were imperfect in 

 form and size, and seedless if not pol- 

 linated with pollen of another variety. 

 Many varieties, especially of plums and 

 pears, will bear no fruit, or very imper- 

 fect fruit, if not cross-pollinated. 



EXPERIMENTS IN MICHIGAN. 



While in Michigan, I tried at the State 

 Agricultural College, numerous experi- 

 ments, as did my friend and colleague, 

 Dr. W. J. Beal, that we mightdetermine 

 just how necessary this cross-pollination 

 might be. Dr. Beal experimented with 

 red clover, and I with red and Alsike 



clover, and with several cultivated 

 fruits, as cherries, plums, apples, pears, 

 strawberries, raspberries and blackber- 

 ries. Sets of blossoms of the same num- 

 ber were marked on contiguous plants 

 or twigs, and one or two of the sets just 

 prior to the opening of the flowers, were 

 closely covered with cheese-cloth, while 

 the other set was left uncovered. 



In several cases it was noted just 

 when the stigmas were ripe, and bees 

 were caught and enclosed in one of the 

 cheese-cloth bags surrounding the 

 flowers. The bees were watched and 

 seen to work on the flowers in several 

 of the experiments. The results pub- 

 lished in the Report of the State Board 

 of Agriculture were surprising. The 

 covered flowers, where bees were ex- 

 cluded gave from no fruit to very little, 

 except in the case of strawberries and 

 blackberries, where there seemed very 

 little difference, while the uncovered 

 and covered, where bees were enclosed 

 in the bags with the blossoms, bore well. 



In some of the cases, as with cherries 

 and plums, the contrast was remark- 

 able. In several of the experiments 

 where bees were admitted under the 

 covers, especially red clover, where 

 bumble-bees were enclosed in the sacks, 

 the fruitage was equal to that of the un- 

 covered plants. 



These experiments seemed to show 

 conclusively that cross-pollination was 

 necessary, and that bees and other 

 sweet-loving insects were a most impor- 

 tant factor in securing a full crop of 

 fruit. 



It has been objected to the above ex- 

 periments, that the very facts of the 

 covers vitiated the results ; that very 

 likely the covers themselves would par- 

 tially or wholly prevent the development 

 of fruit. I would reply that in hand 

 pollination such is not found to be the 

 case, and that in some of the above 

 cases the flowers were covered, and bees 

 caught and put inside the covering 

 sacks, and a good yield of fruit secured. 



EXPERIMENTS AT POMONA COLLEGE. 



Upon coming to this State and county, 

 early this year, it occurred to me that it 

 was very desirable that similar experi- 

 ments should be conducted at this place. 

 That a thing is true in Michigan is no 

 certain proof that it is so under the very 

 different conditions of California. If 

 cross-pollination is essential here, where 

 fruit-culture and bee-keeping alike are 

 important industries, it is very impor- 

 tant that it should be generally known, 

 that the fullest benefits of such knowl- 

 edge may be secured, I therefore com- 



