ADAPTATIONS IN ANIMALS AND PLANTS 



33 



and sunflower. Bees are much more of a factor in fertiliza- 

 tion in the temperate zone than butterflies. It is a general 

 rule that flowers fertilized by the latter are much more con- 

 spicuous than those fertilized by bees. It is generally the 

 case that the time of blossoming of these plants corre- 

 sponds with the appearance of certain insects and in a few 

 cases adjusted to the time of arrival of the ruby-throated 



humming-bird. It has 

 that "arctic flowers be 

 colored in proportion ^ • 

 of winter, insects ^j 

 eration in the act 

 more uncertain 



been asserted by Grisebach 

 come larger and more richly 

 as, by the increasing length 

 become rarer, and their coiip- 

 of fecundation is exposed to 

 chances." ^ 



Why the Nectar Gatherers 

 Assemble on the Bass- 

 wood Blossoms 



.N a warm sunn}' day in the 

 middle of July, the linden tree 

 in blossom affords a centre of 

 attraction for many insects. The 

 sweet perfumed blossoms are scented 

 far and wide by a host of busy httle 

 wanderers that come and congregate 

 there. Such insects as the bumble 

 and the honey bees are seen hanging 

 to the pendent flower clusters, drink- 

 ing the honey, while on the sur- 

 face of the leaves many small 

 flies play in the sunshine, and 

 now and then take their 

 lunch from the flowers. Ar- 

 gynnid and skipper butter- 

 flies participate in the grand 

 Species of bees, flies, and wasps collectively 

 fly out into mid-air about the blossoms at every stir of the limbs 

 and foliage. The birds, too, become aware of this meeting 



convention of life. 



'Wallace, in "Natural Selection and Tropical Nature," p. 407. 



