STATISTICS OF METASPERMAE. 



7i; 



The general parallelism between these tables and those of 

 the generic range-elements need not be noted here in detail. 

 As before, the largest figure is that which indicates the east- 

 ern range-per cent, of the Monocotyledones. The even north 

 and south range of the Monocotyledones is to be observed, 

 together with the preponderant southward massing of the 

 Metachlamydeae. The eastern and western percentages of 

 Metachlamydeae are found to approach each other more 

 closely than such percentages in the other two groups, — in- 

 dicating as before, the comparative lateral solidarity of the 

 Metachlamydeae, to be set over against the comparative 

 longitudinal solidarity of the Monocotyledones. In both cases 

 the Archichlamydeae are seen to occupy the intermediate 

 position. As a whole the metaspermic flora of the Minnesota 

 valley presents itself as distinctly eastern and southern by 

 species as before by genera. The statistics are as follows: 



It is possible, too, from Table D. to determine certain com- 

 pound-ranges, both numerically and by percentages. Upon 

 examining the table it will appear that the following groups 

 may be isolated for study. 



(1) North-East Specific Element. NE. 



(2) North-West Specittc Element. NW. 



(3) North-East-West Specific Element. NEW. 



(4) North-South- West Specific Element. NSW. 



(5) North-South-East Specific Element. NSE. 



(6) North-South-East- West Specific Element. NSEW. 



(7) South-East Specific Element. SE. 



(8) South-West Specific Element. SW. 



(9) South-East-West Specific Element. SEW. 



