Statistics of the Flora of the Northern States. 25 
3 Belong also to Western temperate Asia, viz. Menispermum 
Planera, and Zizania; two of these being peculiar to that 
district and to ours. 
73 Extend southward beyond the limits of the United States 
apd into tropical regions, or recur in the southern hemis- 
ere. 
120 Ke characteristic Eastern United States genera. 
As already stated, only three genera are actually restricted to 
the geographical area comprised in our ‘Botany of the Northern 
United States’. If, however, we allow our area to embrace Can- 
ada, which naturally belongs to it, and also include those plants 
which extend southward much beyond lat. 36° 30’ only in the 
Alleghanies or cool upper country of the Southern States, we 
may enumerate 37 genera peculiar to this flora; viz.— 
Zanthorhiza. Echinocystis. Pyxidanthera. 
Hydrastis. Sullivantia. Direa. 
Caulophyllum. Zizia. Hamiltonia. | 
Diphylleia, Erigenia. Comptonia. 
Jetfersonia. — -  Brachycheeta. Arethusa. 
Adlumia, Chiogenes. Tipularia. 
Solea. Oxydendrum. Aplectrum, 
Huds Sia. - Rhodora. Medeola. 
Napea, Leiophyllum. Helonias. 
Cladrastis, Schweinitzia. Chamelirium 
Gymnocladus, Galax. Amphicarpum 
- Gillenia. Nemopanthes. 
Dalibarda. Hemianthus. 
nerally; and no idea can be formed of the real features of a 
fo ike ours from such a dissection, and piecemeal presentation, 
ach part, 
or from an exhibition of what is strict] y peculiar to eac 
rather than what is predominant,—at least as respects generic 
forms. 
Returning now to the species—the real exponents of vegeta- 
tion;—these have already been considered as regards their nu- 
merical proportions in the several classes and orders of the flora 
of the Northern States: it remains to note some facts respecting 
their geographical distribution. 
SECOND SERIES, VOL. XXII, NO. 65.—SEPT., 1856, 
29 
