714 METASPERMAE OF THE MINNESOTA VALLEY. 
\ 
D. Table Illustrating General Continental Range 
NORTHERN. SOUTHERN. 
agiWanaee pan eewnaladwea ee eed Adopogon virginicum........ 
Lygodesmia juncea...... .....| Lygodesmiajuncea........... 
sane by ctuanautatay oapsolad leans aye ey as Sat Prenanthes serpentaria ...... 
Prenanthes alba.............. Prenanthes alba ............. 
ee ee es Prenanthes aspera........... 
Prenanthes racemosa......... Prenanthes racemosa......... 
Se titeck seeeeeeeeeeeeees+aeee+-.-| Hieracium longipilum........ 
Hieracium venosum........... Hieracium venosum. ......... 
Hieracium canadense..........[. 0c ccc c ccc eee tener e eines 
Before proceeding with the range statistics, a table of gen 
eral statistics is herewith presented: 
15. Representation of Species. 
No. of Per cent. of all |Av. no. of species} 
species. species. per genus. 
Monocotyledones...... 334 28.4 3.15 
Archichlamydeae..... 459 39.1 2.63 
Metachlamydeae...... 381 32.3 2.97 
. : General av. no. per| 
Total no. val. species.| 1174 [...... eee eee eee genus...... 2.87 
The larger average per cent. of species to the genus in the 
Monocotyledones is due to the influence in that group of the 
genus Carex, among other conditions. In addition, the general 
dispersion which has been supposed to mark the taxonomic 
group of the Monocotyledones in particular, has doubtless its 
influence on the average number of species per genus. Passing 
next to the statistics condensed from Table D, we isolate first 
the four principal range elements. These are: 
(1) The Northern Specific Element. 
(2) The Southern Specific Element. 
(3) The Hastern Specific Element. 
(4) The Western Specific Element. 
