I. INTRODUCTORY EXPLANATIONS. 
Puyro-croaraPuy traces out the history and distribution of 
plants, in connexion with the geographical position of countries, 
their conditions of climate, and the physical peculiarities of their 
surface. It has been more specially described under two names 
or divisions, according to the different modes in which the subject 
matter is chiefly taken under consideration. 1. Geographical 
Botany is understood to begin with the plants themselves, whether 
by individual species or in generic or ordinal groups, and to trace 
the distribution of the species or groups over the surface of the 
Earth, or over any portion of it immediately under consideration. 
2. Botanical Geography regards the Earth’s surface itself pri- 
marily, and examines the floral peculiarities of its various parts or 
divisions ; investigating the diversities and correspondences of 
their respective floras, and endeavouring to ascertain the circum- 
stances or influences which have determined the existing con- 
ditions of plant-distribution. Briefly, the former may be said to 
treat about the places of the plants; the second, conversely, to 
treat about the plants of the places. If reduced into brief 
questions, the distinction may become still more clear. 1. In 
what places, and under what conditions, does this plant or group 
of plants occur ? 2. By what kind of plants, or combination of 
plants, is this country inhabited and characterized ?—how did 
they first get to it?—how maintained there ? 
This present volume will be devoted to geographical botany. 
Each British species will be treated separately and successively, 
and its geographical distribution will be indicated in accordance 
with a fixed form. The ample details thus condensed within a 
B 
