THE ANATOMY OF THE NODE IN ANGIOSPERMS 321 
The chief importance of a comparative study of the node will 
consist in providing us with evidence whereby we may group related 
families together into orders which shall be more natural than the 
present ones. No one character is, of course, sufficiently constant 
to be made the sole basis of such a reclassification. The structure of 
the node is not always invariable, by any means, and further study 
will doubtless reveal numerous exceptions to the foregoing brief 
outline and make necessary many changes in it. The value of such a 
character as this, however, is that, compared with many others, it is 
extremely constant and very simple. 
The present paper, which is based on a study of only about four 
hundred genera, is but a brief indication of what are some of the main 
facts which a comparative study of the node brings forth. A very 
much more thorough and extensive investigation will be necessary 
before we shall be able to say to just what extent nodal anatomy may 
be made useful in classification. That it will assume an important 
position in the final construction of the phylogeny of the angiosperms 
appears to be reasonably certain. 
The writer wishes to express his thanks to the authorities of the 
Harvard Botanical Garden and of the Arnold Arboretum for use of 
material in their collections. 
BussEY Institution, 
Harvard University. 
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