Record. xxxi 



by artificial cooling or by a narcosis. Consequently the 

 growing season can be secured much earlier than usual. 



Far more interesting is the influence of man upon species, 

 depending upon fluctuating variability and mutation. While 

 selection cannot produce a constant species, it helps us to 

 keep up the standard. 



The most wonderful achievements have been obtained by 

 hybridization. As a result of crossing, flowers and fruits 

 with which we are familiar, are very different from the wild 

 varieties; so changed, in fact, that we do not recognize them 

 unless trained botanists. 



Among the living botanists, who have been successful in 

 producing hybrids, is Burbank of California. His aim is to 

 produce plants with shipping qualities and such as can be 

 grown in regions which are now little used for cultivation. 

 One of the things he has worked out is the " Thornless 

 Cactus," which can be grown on the deserts of Arizona and 

 New Mexico and forms excellent cattle food for dairies. This 

 hybrid Burbank obtained by crossing a certain species of 

 Mexican cactus with a certain species from South Africa. 



Hybridization is not successful, however, if the two plants 

 taken are too widely separated in their characteristics. Either 

 no seed is formed, or hybrids are produced, which are not 

 fertile; strawberries, when crossed with blackberries, produce 

 a variety with flowers but no fruit. The best results are 

 obtained by combination. 



May 15, 1905. 



President A. Alt in the chair; attendance fourteen. 



The President announced the death, on May 13th, of Mr. 

 Edwin Harrison, a patron and former president of the 

 Academy. Prof. F. E. Nipher, Dr. G. Hambach and Mr. 

 E. P. Olshausen were appointed a committee to prepare reso- 

 lutions commemorative of the deceased. On motion of Dr. 

 Hambach the Secretary was instructed to request Prof. G. C. 

 Broadhead of Columbia, Mo., to write a biography of Mr. 

 Harrison for publication in the Proceedings of the Academy. 



