Bulletin - United States National Museum - Smithsonian Institution

36 FLORA OF WASHINGTON AND VICINITY.
to other parts of the United States.* These are distributed through
the several larger groups as follows
"Polypetalous
Gamopetalous
Apetalous (Monochlamydeous) . .
Monocotyledonous (Endogenous)
Gymnospermous (Coniferous)
Total
.
.
Groups.
:
Old
World.
United
States.
Total.
178 15 193
It will be seen that the introduced plants amount to 15.5 j)er cent, of
the total flora. The several orders to which these belong are shown in
the Summary.
Shrubby Species.
Of the 342 " forest trees " enumerated in Sargent's preliminary cata-
logue of 1880, this flora embraces 85, or 24.8 per cent., of which 65 are
large enough to have the dignity of timber trees. Of these 85, 25 are
in the Polypetalous Division, but only 12 of this latter number are
large; 9 are in the Monopetalous Division, all but 2 of which are large;
44 are in the Apetalous Division, 39 of which are large; and the remain-
ing 7 are Coniferous, all full-sized trees.
The whole number of species which are shrubby or woody above
ground is 194, which is 15.5 per cent, of the whole. They are distrib-
uted as follows
:
Polypetalons 83
Oamopetalous 36
Apetalous (Mouoclilamydeous) 64
Monocotyledonous (Eudogeuous) 4
vGymnospermous (Coniferous) 7
Total..: 194
'For further i)articulars the reader can consult the Summary at the
»end of the catalogue.
Gomimrisons with other Floras.
While these facts are of great interest in afibrding a clear conception
of the character of our flora, they do not aid us in determining in what
respects it is peculiar or marks a departure from those of other portions
* These are the following :
XanthoxyluniAmericanum. Ribes rotundifolium. Catalpa bignonioides.
Trifoliuni repens. Ribes rubrum. Maclura aurantiaca.
Prunus Chicasa. Passiflora incarnata. Populus grandidentata.
Rosa setigera. Symphoricarpusracemosus. Poa annua.
Philadelphus inodorus. Symi>horicarpu8 vulgaris. Pinus Strobus.