vi ' PREFACE TO THE FIFTH EDITION. 
Demonstrator of Practical Biology in King’s College, London, 
for the valuable assistance he has rendered generally, but more 
especially for, in a great degree, revising the Third Book on 
Physiology. In this edition, so far as the above subjects are 
concerned, the standard works of Sachs, De Bary, Eichler, 
Strasburger, Van Tieghem, Luerssen, Vines, and Bower have 
been more particularly consulted, besides a large number of 
original memoirs published in this country and elsewhere. 
In the part treating of the properties and uses of plants, 
many alterations have been also rendered necessary by the pro- 
gress of science, and the recent issue of a new edition of the 
‘British Pharmacopeeia.? The very large number of plants to 
be here noticed has compelled the author to be very brief in 
his descriptions of them individually ; but so far as the principal 
plants employed in medicine are concerned, those readers who 
require more detailed information are referred to Bentley and 
Trimen’s ‘ Medicinal Plants,’ where coloured figures, botanical 
descriptions, and other fall particulars may be found ; and to 
Fliickiger and Hanbury’s ‘ Pharmacographia.’ 
While the work in all the above particulars has awe been 
very carefully revised, the most marked change that will be 
noticed is in the part relating to the Classification of Plants, 
which, so far as the Phanerogamia are concerned, has been very 
materially modified, and in some parts rewritten, in order to 
adapt it in all essential particulars to the arrangement adopted 
in the great work on that subject, the ‘Genera Plantarum’ of 
Bentham and Hooker, which has been published in a complete 
form since the last edition of this Manual was issued; and 
which cannot fail to be the standard work on the subject for 
many years. Important changes have also been made in the 
Classification of the Cryptogamia, but, so faras these plants are 
concerned, their arrangement at present must be regarded as 
transitional ; and hence, as their full description is beyond the 
scope of this Manual, advanced students must refer to special 
treatises for detailed notices of the arrangement and characters 
of the several groups of the Cryptogamia, and more especially 
of the Thallophytes, 
The present edition having been thus carefully revised in all 
its parts, adapted, as far as possible, to the present state of 
botanical science, and supplemented by very copious and care- 
fully prepared indexes, which have been kindly prepared for 
