456 



THE AMERICAN NATURALIST. [Vol. XXXVII. 



Summary and Conclusions. 



Xumcrical Summary . — In the territory extending northward 

 from the parallel of the northern boundary of North Carolina 

 and Tennessee to the northern limits of Labrador and Manitoba, 

 and from the Atlantic Ocean westward to the I02d meridian, 

 there are recognized in the Illustrated Flora of Britton and 

 Brown 4020 angiospermous plants. In the following table the 

 species belonging to the different series have been arranged 

 according to their predominant floral colors. 





Green 1 White 













'Dicotyledons 

 ' ChoripetalK 



Apetal* . . 



Ga^opeUlaT ' 



8 57 82 



■n * 



72 375 





106 





57 



1058 



384 

 [ 2 3 6i 



Total . . 



1244 956 





2 57 



437 



325 





In every 100 species there are 30.9 green, 23.8 white, 19.9 

 yellow, 06.4 red, 10.9 purple and 08. blue. The hydrophilous 

 and anemophilous species within this area, I place at about 1048, 

 of which 1 02 1 are green, 1 white, 1 1 yellow, 3 red and 1 2 

 purple. A number of spec ies vary between wind-fert ili/.at ion 

 and insect-fertilization, and are differently classed by different 

 observers. Empctntm nigrum according to Warming is a wind- 

 flower, according to Lindman an insect flower, and according to 

 Knuth it is a wind-flower with occasional insect visits. There 

 are then in the district under consideration 2972 species, which 

 are fertilized by insects or are self-fertilized. Of this number 

 223 are green, 955 white, 790 yellow, 254 red, 425 purple, and 

 325 blue. In every 100 of these plants 07.5 are green, 32.1 

 white, 26.6 yellow, 08.5 red, 14.3 purple, and 10.9 blue. It is 

 evident that anemophily and small greenish flowers are corre- 

 lated, and that large bright colored flowers are due to insect 

 fertilization. The 1048 Anemophilae and Hydrophilas are dis- 



