INTRODUCTORY ESSAY. 9 



them ; and as we trust that our work will fall into the hands 

 of many beginners who are anxious to devote themselves use- 

 fully to the furtherance of botanical sciencej but who have not 

 an opportunity of acquiring in any other way its fundamental 

 principles, we shall make no excuse for dwelling at some length 

 on the subject. We are also anxious to refute the too com- 

 mon opinion {which has been productive of much injury to 

 the progress of botany) that the study of system presents no 

 difficulties, and that descriptive botany may be undertaken by 

 any one who has acquired a tolerable familiarity with the use 

 of terms. 



There can be no doubt that any observant person may rea- 

 dily acquire such a knowledge of external characters, as wUl 

 in a short time enable him to refer a considerable number of 

 plants to their natural orders ; though even for this first step 

 more knowledge of principles is required, than to make an 

 equal advance in the animal kingdom : but to go beyond this, 

 — to develop the principles of classification, to refer new and 

 obscure forms to their proper places in the system, to define 

 natural groups and even species on philosophical grounds, and 

 to express their relations by characters of real value and vrith 

 a proper degree of precision, demand a knowledge of morpho- 

 logy, anatomy, and often of physiology, which must be com- 

 pletely at command, so as to be brought to bear, when neces- 

 sary, upon each individual organ of every species in the group 

 under consideration. To follow the laws that regulate the 

 growth of all parts of the plant, especially the structure of 

 stems, the functions of leaves, the development and arrest of 

 floral organs, and the form, position, and minute anatomy of 

 the pollen and ovule, and to trace the whole progress of the 

 ovule and its integuments to their perfect state in the seed, 

 ought all to be familiar processes to the systematic botanist 

 who proceeds upon safe principles; but no progress can be 

 made by him who confines his attention chiefly to the modifi- 

 cations of these organs in individual plants or natural orders. 



To many all this may appear self-evident, and we should 



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