THE BOTANISTS OF PHILADELPHIA. 381 



In a paper * entitled " Notes on the Cross-Fertilization 

 of Flowers by Insects " (Proceedings Academy Natural Sciences, 

 Philadelphia, 1S9G), Dr. Keller boldly challenged the asser- 

 tions of Darwin and others, that cross-fertilization of flowers 

 is of utmost value to the individual species, and supports 

 the contention of the opposing school that the great bulk of 

 colored flowering plants are self-fertilized ; that self-ferti- 

 lizers are every way as healthy and vigorous, and immensely 

 more productive than those dependent on insect aid ; and, 

 finally, that where plants are so dependent, they are the 

 worst fitted to engage in the struggle for life, the great 

 underlying principle in natural selection. As a result 

 largely of Dr. Keller's paper, the Gardener's Chronicle, com- 

 menting on her deductions, says : 



" It will certainly be somewhat of a shock to some 

 conservative people to hear that the cherished convictions 

 have been ruthlessly undermined. It seems we must give 

 up believing that nature loves cross-fertilization, and adapts 

 herself to it, and that the lovely hues of flowers are due to 

 insects. The evolutionist must set to work and get some 

 new theories to suit these Jin de siecle opinions. How can 

 we account for the beautiful colors and beautiful scents 

 which please our senses, but apparently do not please 

 insects at all ? We must have more experiments before the 

 question of relation between flowers and insects can be 

 satisfactorily settled." 



BIBLIOGRAPHY. 



1. "Tiber die Protoplasma Stromuug im Pflauzenreich." Zurich, 

 1890. 



2. '"The Phenomena of Fertilization iu the Flowers of Mouarda 

 fistulosa." Proceedings Academy XithirnJ Sciences, Philadelphia, 1892. 



* See editorial, Public Ledger, Thursday, October 29, 1896. 



