Climate of Middle Illinois. 



71 



A number of local floras and sucli of larger districts of the same geo- 

 graphical latitude or longitude are given in the following table, but it 

 must be remarked that all mere varieties and all introduced species are 

 excluded, and that the figures mean the number of the entire states, even 

 if they, like New York state, Ohio, Illinois, and Wisconsin, belong to dif- 

 ferent natural floral districts: 



The comparatively large number of species in Illinois is readily 

 explained by the wide extension of this state in a south-north direction 

 over 5° of latitude. The number of species in * Michigan, Wisconsin, 

 Arkansas, and particularly in Colorado may really show greater figures, 

 as those states are apparently not so thoroughly explored in all parts. 



Generally the eight or ten largest orders make up half of the whole 

 number of vascular species of a floral district. The following tables will 

 show the per mille of species for each of the largest orders: 



Massachusetts. 



Cyperacese 116 



CompositiB 108 



Graminete 73 



Kosaceae 38 



Ericacea; 33 



Filices 32 



Leguminoste 26 



Orchidaciv 26 



Scrophulariaceae 24 



Labiatie 22 



498 



Neiu York. 



Cyperaceae 113 



Compositse 104 



Graraineffi 79 



Rosaceie 36 



Leguminosfe 34 



Ericaceae 30 



Filices 30 



Orcliidacete 29 



ScrophulariaceiE ... 25 



Labiatse 25 



505 



OJiio. 



Compositie 122 



Cyperaceie 95 



Graminete 65 



Leguminoste 40 



Rosacete 36 



Orcliidacea) 32 



Filices 30 



Ranunculacese 29 



Labiatse 28 



Liliacese 28 



505 



* * Michigan means here the lower peninsula, and the flora is taken from the 

 first Report of Geological Survey of Michigan, 1861. The flora of Wisconsin after 

 Lapham's Catalogue in Transactions of the Wisconsin State Agricultural Society, 

 1853, with two additions by Hale. The flora of Arkansas is after Lesquereux' 

 Catalogue in Arkansas Geological Survey US^O). The flora of Colorado is after 

 Porter and Coulter (1874). 



