MO THS — II UM MING-BIRDS. 93 



tion of the flower. The bee lights upon this 

 lower portion, and its weight forces the pet- 

 als down, while the stigma, carrying pollen 

 from the surrounding anthers on its hairy 

 style, protrudes and strikes the bee and 

 dusts it with pollen. 



Many flowers are especially fitted for fer- 

 tilization by moths. Such are most of the 

 long-tubed flowers. As most of the long- 

 tongued insects are nocturnal, so many of 

 the long-tubed flowers open only at night, 

 and they are furnished with light colors that 

 they may be seen in darkness. Many of 

 them exhale strong perfumes at nightfall, as 

 the petunia. As the moths whir about the 

 petunias, and the evening primroses, and 

 other flowers at nightfall, think what attrac- 

 tions the plants offer the insects, and what 

 advantages they expect to derive from their 

 visits. Some long - tubed flowers are fer- 

 tilized by humming-birds. This is at least 

 sometimes the case with the flowers of the 

 trumpet creeper. Some flowers possess pu- 

 trid odors to attract flies, as the common 

 herbaceous smilax or carrion-flower. A few 

 are fertilized by snails. 



There is no doubt that in most cases close- 

 fertilization is a direct disadvantage to the 



