330 COLLEGE BOTANY 



tropical. Many of them are remarkable for their most beautiful 

 flowers. Many of the flowers are especially adapted for pollina- 

 tion by certain insects. One tropical American genus ( Vanilla ) 

 contains two species from which the vanilla of commerce is ob- 

 tained. Many other species are grown because of their great 

 beauty. This family is represented in our north temperate zone 

 by a great many species. The genus Cypripedium, which includes 

 the lady's slipper or moccasin flower, is one of the best known. 



