732 METASPERMAE OF THE MINNESOTA VALLEY. 
form 36.5 per cent. of the extra-continental species; while the 
Archichlamydeae form 31.9 per cent. of the total species they 
form 41.0 per cent. of the extra-continental element, and while 
the Metachlamydeae form 32.3 per cent. of the total flora, they 
form but 22.5 per cent. of the extra-continental element. This 
element shows, when compared with the general flora, a fall- 
ing off in Metachlamydeae and a concurrent increase of Mono- 
cotyledones and Archichlamydeae. The increase is greatest 
among the Monocotyledones. 
In the second of the last three tables the distribution by 
countries of the extra-continental element is indicated. The 
percentages are fairly exact except in the case of the West 
Indies. Of this region access has been had only to Grisebach’s 
Flora of the British West Indies. The percentage is probably 
somewhat too small, but would in any event be likely to be the 
smallest of the series. It is seen that the extra-continental ele- 
ment is preponderantly Asiatic, and of the Asiatic group the 
Manchurian-Japanese forms a considerable percentage. Sub- 
tracting this percentage from the total Asiatic percentage gives 
54.2 per cent. as the approximate Siberian element. This divis- 
ion of the Asiaticelement is a proper one and the two groups 
of extra-continental species thus isolated would be interesting in 
detailed comparison. Such comparison would, however, be a 
little removed from the purpose of the chapter. A glance at 
the table will show several curious facts that may be noted. 
The Siberian group furnishes a larger percentage of Monocoty- 
ledones and smaller percentage of Metachlamydeae, compara- 
tively, than the Japanese-Manchurian. The African element 
is almost as large as the South American or Australasian, and 
for the most part consists of the same plants. In all three the 
preponderant taxonomic group is the Monocotyledones, and of 
these it is especially the aquatic or marsh forms that are thus 
widely distributed. In these three distant elements the mono- 
cotyledonous percentage is somewhat in advance of such gen- 
eral percentages of the whole extra-continental element. 
Especially in the most distant element, the Australasian, are 
the Monocotyledones predominant. Of this element they form 
66.6 per cent. Of the European element the Monocotyledones 
form a larger percentage than of the Asiatic, while of the 
Asiatic element the Archichlamydeae and Metachlamydeae form 
each a larger percentage than of the European. Of the Man- 
churian-Japanese element the Archichlamydeae and Metach- 
lamydeae each form a larger percentage than of the Siberian 
or total Asiatic. 
