320 THE PARTS OF A SEED-PLANT 
to show not a little variety and complexity in the different 
parts which compose it, and one is aware that much more 
complexity of structure would appear upon further study. 
But why the plant should have such a complex structure 
may not be at first so obvious. We are helped to an under- 
standing of the matter, however, by remembering that 
wherever there is much variety of work to be performed, it 
is an advantage to have the labor divided among different 
sets of workers, each fitted for their special share and codperat- 
Fic. 280.—Flax Bud cut vertically and much enlarged to show the develop- 
ment of the leaves from protrusions arising at the side of the dome- 
like stem-tip which consists of formative material. (Original.) 
ing with the rest. This principle is shown clearly in the com- 
munity to which we belong, where the labor of meeting the 
needs of the people as a whole is divided among farmers, 
miners, manufacturers, merchants, soldiers, teachers, and 
many other classes, while in each class the work is divided 
and subdivided again and again. The degree of specialization 
and codperation found in such advanced communities as our 
own chiefly distinguishes them, as we know, from such less 
advanced communities as the Indian tribes which preceded 
us upon the American continent; and we say that this was 
