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of the various groups and the more important plants contained 
in them. The first represents information which the successful stu- 
dent should carry with him permanently; the second a mass of 
statistics which are best carried in a conveniently available book 
of reference rather than in the student’s memory. We all realize 
that it is beyond the power of any person to know all the hun- 
dred and fifty thousand species of flowering plants, or the thou- 
sands of genera, and we doubt if even such men as Hooker or 
Engler could place any plant into its proper family at sight. With 
most of us, lack of contact with possibly half of the three hun- 
dred families soon dims them in our memory, but every botanist 
should recognize at sight at least twenty-five of the larger families, 
excepting of course the aberrant members, which often baffle even 
the specialist. But if he has the general principles well in mind, 
and has access to a proper reference book, he should soon be able 
to locate any other plant in its proper group. This seems to be the 
goal which Dr. Johnson would reach in his teaching, and with it 
we are heartily in accord. 
We have no doubt that one of his students will recognize with- 
out difficulty a composite, an umbellifer, a crucifer, or members 
of many other families at sight, no matter where he finds them, 
but we wonder whether that recognition will come as a result of 
the application of the general principles presented in the book, or 
by comparison of the flower with the recollection of other flowers 
which he has seen in his field or laboratory work in Dr. Johnson's 
class. For example, if a student traveling in South Africa is at 
tracted by a handsome tree with silvery foliage, will an examina- 
tion of the flower convince him that he is dealing with the Pro- 
teaceae, having a specimen of Leucodendron before him? As a 
still more difficult case, consider the family Flacourtiaceae, which 
contains a remarkably diverse assemblage of plants. According to 
Dr. Johnson, the flowers may be hypogynous, perigynous, OF 
epigynous ; the sepals 2 to 15; the petals none to 10 or more, the 
stamens few to many, free or united in bundles; the carpels 2 to 
10. We wonder if a student can place a plant in this family ac- 
curately, or even in the order to which it belongs, and if he should 
guess the family, whether he can verify his guess by reference t0 
any information about it which Dr. Johnson gives. Reference t0 
his chart on page 150 indicates that the Parietales, to which the 
Flacourtiaceae belong, have sepals and separate petals. How can 
