Tree Life 
to a great extent the following groups present substan- 
tially the affinities recognized by rigid science: and— 
as our present purpose is not to teach botany, but 
simply to help the reader to enjoy nature—we do not 
feel obliged to apologize for the few discrepancies. A 
bird’s-eye view of the trees of the Northeastern United 
States is all that we are here attempting to present. 
A few simple but interesting facts in flower-structure 
will make the principle of our classification apparent. 
All trees produce flowers, that outgrowth that even- 
tuates in fruit of some sort ; but the flowers are of two 
very distinct sorts; one found in deciduous trees 
«shedding their foliage in fall), the other in evergreens ; 
but here the distinction of foliage suffices to differen- 
tiate the two groups. 
In the flower-type of the great deciduous group, con- 
taining all except evergreens, and comprising more than 
nine-tenths of all our species, a complete blossom con- 
sists of four distinct parts—calyx, corolla, stamens, and 
pistil; and the evolution of this type from the simplest 
to the most elaborate form shows a most interesting 
series of gradations. Lowest in the scale are those 
trees whereon one flower consists only of a few stamens 
containing pollen, another of only a pistil or seed-case 
to be fertilized by the pollen, neither of these flowers 
with the slightest vestige of either calyx or corolla 
(which botany calls the ‘ floral envelope’’ of the blos- 
som). Willows and poplars produce this rudimentary 
flower. 
A little higher in the scale such staminate and _pistil- 
late flowers as we find in willows have a rudimentary 
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