"- editing them pains have been taken to avoid, as far as pos- 
af ~ sible, the putting forward of geological or geographical 
Reo MALL | Preface. 
_ The seventh and eighth chapters have hee considerably 23 : 
ae compressed, and some portions have been altered. In | 
‘ theories as demonstrated truths. The young student cannot 
be too cautious about forming or adopting theories, except 
as mere modes of classifying facts, which must be modified — 
~-as our knowledge of facts increases. Some general notion 
- of the distribution of plants in space and time is essential to 
him ; but he should, as far as possible, check and correct 
bey _his theories by getting together and collating a large fund of 
: - observation. The chapter on the Geographical Distribution 
of Plants is a brief epitome of Grisebach’s conclusions, as _ 
stated in his ‘Vegetation der Erde,’ of which there is as yet 
no English translation. All editorial additions throughout: 
the work are distinguished by being placed. between square 
3 brackets. 
It would be impossible, even were it desirable, to define, 
in an elementary work of this kind, every scientific term in 
‘use by every writer ; many of those not mentioned in these 
pages carry their own explanation with them. Some addi-_ 
~~ tions have been made by the editor to those included in the 
original work ; and it is believed that every term necessary 
to the young student will be found defined either in the text _ 
or in the glossarial index at the end. Reference is made, 
in this index, not only to the pages where an explanation of 
ee fade is illustrated. In the Latin names of British plants, the 
‘used. eee 
each term will be met with, but also to every figure in which 
one adopted in Hooker’s ‘Student’s Flora’ is in all cases ie 
, In conclusion, the editor desires to call the reader’s at- i i 
a tention to one or two important memoirs which have been pare 
