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THE AMERICAN BOTANIST. 



It may be said here that annual plants are annuals, not so 

 much because they cannot survive the rigors of winter, as be- 

 cause they die of exhaustion due to seed-bearing ; indeed, many 

 plants that survive the cold and storms of winter as mere seed- 



HELIANTHUS SCABERRIMUS 



lings, die in the midst of summer's plenty having used all their 

 strength in the production of flowers and fruits. Many an 

 annual which ordinarily completes its life-cycle in a few weeks 

 or months in the milder part of the year will, when planted 

 late in autumn, thus survive the winter as a "winter annual." 

 The century plant (Agave) is typical of still another phase 

 of plant life. In this, the plant gathers strength for several 

 years and then finally blooms, fruits and dies but not before it 



