IV 
INTRODUCTION. 
theory or system, with which of course the student must be 
acquainted, before he can appreciate the worth of any personal 
observations lie may chance to make. On my plan, any person, 
with a little care, may become a tolerably good naturalist, the 
first walk he takes in the fields, without much knowledge of' 
books : on the other, much previous study is indispensable, while, 
as I shall endeavour to show, this will often be labour thrown 
away, as it is usually more apt to mislead than to assist. On my 
plan, the student is a free agent ; on the other, he is chained to 
the ranks of the monopolists of knowledge. 
III. As systems and classifications have so long usurped almost 
the exclusive attention of those who have attended to the objects 
of nature, it appeared necessary to give the student some notion 
of the proper use of a system, in order to prevent his falling into 
the error of looking at a system in a false light. I have there- 
fore thought it important to speak plainly and strongly upon this 
subject. 
IV. In giving an estimate of the Linnsean system, I have en- 
deavoured to place the merits of its distinguished author in a just 
point of view ; while I have quoted, to fortify my own opinion, the 
sentiments of several able naturalists condemnatory of his me- 
thods, or rather of the use to which these have been preposterously 
turned by his disciples. 
V. Among the various systems claiming to be natural, I have 
chiefly directed the attention of the reader to the doctrine of 
Types^ and the Qidnary arrangement founded upon it ; because, 
though it is not exclusively English, being adopted by Denis, 
Scheififermuller, and other continental writers — the disciples of 
Mr. MacLeay speak of themselves as constituting the modern 
English school. I have judged it my imperative duty to object, 
in the most explicit manner, to the doctrines and the language of 
this school ; but while I have considered no terms too strong in 
urging my objections to the Quinary or Typical system, I have 
given all due credit to the upright intentions of its author and his 
disciples, some of whom I have the honour of ranking amongst 
my friends, and to whom I shall be sorry if the remarks I have 
