Part II comprises two chapters, one devoted to the crude drugs official in the United States Pharmacopeeia, including a few non-official drugs, and another which treats of the subject of powdered drugs and foods. The latter is designed not only for the use of students but also to furnish assistance to food and drug analysts in identifying and estimating the quality of vege- table powders, and includes a description of the distinguishing histological elements of over two hundred food, spice and drug products, together with directions for making examinations of materials of this kind.
In Part III are given the various classes of reagents, together with the technique involved in sectioning and the mounting of specimens. In addition various tests are given in connection with different subjects in other parts of the book.
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4 PREFACE.
The work is illustrated throughout, and the student is advised to consult the illustrations freely, not only on account of their value in elucidating the descriptions, but also because the legends contain information which in some instances supplements that given in the text.
It should be stated that a large proportion of the illustrations are reproductions of photographs and drawings made by the author, and that in all cases where illustrations are borrowed, credit is given each author in connection with the reproduction.
One of the most difficult questions which arises in writing a work of this kind is that relating to nomenclature. Owing to the desirability of maintaining a stable nomenclature, particularly for medicinal plants, the author has adopted a rather conservative course and has been largely guided by Engler & Prantl and Index Kewensis, or, in the case of plants growing in the United States, the names given in Britton’s Flora may have been employed.
Among the works consulted by the author, and of which special mention should be made, are the following: Organography of Plants by K. Goebel (English translation by Isaac Bayley Bal- four); The Physiology of Plants by W. Pfeffer (second revised English edition by Alfred J. Ewart) ; Die Heilpflanzen by Georg Dragendorff; The Volatile Oils by Gildemeister & Hoffmann (English translation by Edward Kremers); Die Pflanzen- Alkaloide by Jul. Wilh. Brihl, E. Hjelt and O. Aschan.
Grateful acknowledgment is also made to the following pub- lishers for permission to reproduce illustrations from the works mentioned. Wilhelm Engelmann, of Leipzig: Die naturlichen Pflanzen-familien by Engler & Prantl. Gebriider Borntraeger, of Berlin: Handbuch der systematische Botanik by E. Warming. Weidmannsche Buchhandlung, of Berlin: Wissenschaftliche Drogenkunde by Arthur Meyer. Gustav Fischer, of Jena: Lehr- buch der Botanik by Strasburger, Noll, Schenck and Schimper.
The author desires fully to acknowledge the services of Miss Florence Yaple, without whose painstaking and constant assist- ance during the course of revision, this book could not have appeared in its present enlarged form.
H. K. April, 1907.
CONTENTS.