PREFACE TO THE SECOND EDITION 
The appearance of the United States Pharmacopoeia IX and the 
National Formulary IV, with the many changes in the lists and 
definitions of officially recognized vegetable drugs made it necessary 
to revise the former edition of this work. 
In the course of revision, the writer has taken cognizance of the 
growing importance of Botany in the curricula of pharmaceutical 
institutions and has accordingly expanded upon the subject matter 
of the former text. 
With the adoption for the first time by the new United States 
Pharmacopoeia of pharmacognic standards for numerous drugs, 
Pharmacognosy has risen to the forefront in this country as a science. 
While its proper comprehension requires laboratory instruction in 
chemistry, physics, and crystallography as well as botany, neverthe- 
less a rather extended foundation in structural botany stands out 
preeminently as the most needed requirement. 
The work has been for the most part remodeled. Chapter I deals 
with Fundamental Considerations. Chapter II is devoted to the 
life history of the Male Fern, a median type of plant, the considera- 
tion of which, after the students have received fundamental practice 
in the use of the microscope, the writer has found commendable, for 
it not only gives the beginner a working knowledge of structures and 
functions, the homologies and analogies of which will be met in the 
later study of forms of higher and lower domain, but holds their 
interest on account of its economic importance. 
The life history of a type of Gymnosperm, White Pine, is next 
taken up in Chapter III. Chapter IV considers the life history of an 
Angiosperm as well as codrdinates the resemblances and differences 
between Gymnosperms and Angiosperms. Chapters V, VI and 
VII are devoted respectively to Vegetable Cytology, Plant Tissues 
and Plant Organs and Organisms. Among the many additions to 
the topics included in these might be mentioned a treatise on Cell 
Formation and Reproduction including Indirect Nuclear Division, 
