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The Use of Anatomical Characters . 
numerous specimens of each species and a careful comparison of 
the relative value of the different features observed. Vesque has 
likewise contributed greatly towards the anatomical method in 
classification and has shown its value in a large number of orders. 
In recent years large numbers of papers on the systematic anatomy 
of various orders and tribes has been published, which, although 
many suffer very considerably from a one-sided treatment of the 
subject, have still served to extend our knowledge and to establish 
firmly the right of existence of the anatomical method in 
taxonomic botany. The fact of its adoption in the Natiirliche 
Pflanzenfamilien alone speaks for the recognition of its 
importance. 
The anatomical characters of the vegetative organs, and more 
especially those of the leaf, are known to undergo very considerable 
variation according to the habitat of the plant, and moreover, in 
different species, different characters will be subjected to this 
variation. Constancy of all features can only be expected in species, 
all the individuals of which live under absolutely uniform conditions, 
and this rarely occurs. It is therefore of the utmost importance to 
examine a number of specimens from localities diverging as widely 
in character as the distribution of the species allows of, before any 
special anatomical feature is taken as characteristic of the species 
in question. Further, it must not be overlooked, that, just as the 
external morphology often affords few points for the distinction of 
closely related species, their anatomy may also be so similar as to 
render a separation on its grounds unfeasible. In no case can we 
depend on anatomy alone in generic and specific distinction, but if 
we take it hand-in-hand with the external characters we shall very 
frequently find that the two supplement one another in a most 
agreeable manner. Whoever endeavours to classify on anatomical 
characters alone will meet with greater difficulties than the purely 
morphological systematist of the old school. A truly scientific 
classification can moreover only be based on a complete knowledge 
of all the structural features of the plant. 
One of the greatest objections that has been made to the 
anatomical method is the length of time involved in the determinal 
tion of a plant by its means. As a matter of fact, however, the time 
required is not or very little greater than that usually taken in the 
dissection of a flower; in most cases a surface section from the upper 
and lower sides of the leaf and a transverse and rough longitudinal 
section of a branch, all of which with some little practice can be 
