might be raised to such a procedure, as would be the case with '% 
street trees, park trees, and cultivated trees in general. If fruit * 
characters are needed for identification and no fruit can be found 
on the tree, search the ground directly beneath for old 
fruits. If any are found, they may, under normal conditions, be 
regarded as having dropped from the tree, unless the fruit is 
easily blown by the wind, or the ground is sloping and other 
trees grow higher up the slope where fruits might easily roll 
down. 
In using the key begin with No. 1 and read the two lines 
preceded by this number, deciding which one of the two applies 
to the tree under consideration. If the leaves of our tree are 
flattened (as most leaves are) we next pass to No. 2, as indi¬ 
cated by the figure 2 following this line, and read the three lines 
numbered 2, deciding which one of these three applies to our 
tree, passing again to the number indicated after the line 
selected. This simple process is repeated until we reach one or 
more common names in full faced type. If a number is 
found after this name (as in No. 5) it means that the name is 
that of a genus including two or more species. In order to 
decide which species, we pass to the number indicated and pro- ^ 
ceed as before. To illustrate this, suppose we reach No. 5 in ' 
the key, deciding that we have a Pine, we next turn to No. 75 
in order to find which Pine. Preceding No. 75 will be found a 
few briefly stated characteristics of the Pine genus. A similar 
characterization will be found preceding the other genera con¬ 
taining more than one species. Finally we arrive at a point 
where no number is indicated after the line chosen. The 
common namc (or names) will here be found in full faced type, 
and the scientific name in Holies. If more than one common 
name appears the first is usually preferred, the subsequent ones 
being either less distinctive, less common, or merely local in 
some parts of New England. 
Where conflicting opinions exist in regard to specific limita¬ 
tions those laid down in the 7th edition of Gray’s Manual have 
usually been adopted, particularly in cases of such groups as 
have undergone recent revision (e. g. Thorns, Alders, Birches). 
J.he authors will be glad at any time to receive suggestions 
and correction from those who use this key, with a view of per¬ 
fecting and improving it in the near future. 
