8 
racleum ^ ?iW^ CEnanthe. It will be seen that nearly half of our 
genera are represented by single species; 
The following table shows the general distribution of our 
genera. The first column gives the whole number of species 
found in North America north of Mexico; the second, the number 
of introduced species; the third, those species th.at are strictly east- 
ern, including a single tier of states west of the Mississippi; the 
fourth, those species that are western, that is, from the plains 
w'estward; the fifth, those that are found both east and west, some 
of which ma\ be of wide range, and others southwestern and so 
overlapping the boundary between the two regions; the sixth, 
the number of species accredited to each genus throughout the 
world, as indicated by Bentham & Hooker, somewhat modified by 
the more recent changes. The genera marked with an asterisk 
(*) are endemic. 
i., 
1 
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