INTRODUCTION 
T is by no means easy to generalise our ideas of a plant. 
The Plant World, or Vegetable Kingdom as it is more 
technically termed, includes not only a vast number but 
also a very great variety of forms, of which part only have 
as yet been scientifically described. Seaweeds or Alga, 
Fungi, Mosses, and Ferns all come within the limits of the Vegetable 
Kingdom as well as Flowering Plants ; and, while the number of species, 
or kinds, of flowering plants has been estimated at 100,000, there are 
probably in the world a number of the other four groups which, taking 
them together, is not far short of another 100,000. We are concerned 
here only with the highest, i.e. the most highly organised, of these groups, 
the Flowering Plants, and of these alone there are some 1,860 species in 
the British Isles, if we reckon our British Hawkweeds ( Hieracium ) and 
Brambles ( Rubus ) at about 100 species each, and include about a score of 
plants which grow wild only in the Channel Islands and do not, therefore, 
belong geographically to the British Islands. Obviously, therefore, our 
drawings, representing only about 300 species, are merely a selection ; but 
in choosing those to be included, an endeavour has been made to render 
the series as representative as possible, excluding, however, as perhaps less 
ornamental or less suited to water-colour sketches, the Grasses, Sedges, and 
some minor Families of water-plants. 
While some sort of grouping or classification is necessary if we are to 
deal intelligibly even with three hundred plants, it has been found possible 
by a careful scrutiny of all the external structural characters to arrange 
them in an order approximately natural , so as to express to some extent 
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