PRINCIPLES OF BOTANY 



INTRODUCTION 



Botany is the science which treats of plants. It considers the 

 structure and functions of individuals, recognizes their neighbor- 

 hood relations as citizens of plant communities, and studies their 

 positions as members of the plant kingdom more or less closely 

 related by common descent. The study of the individual plant 

 embraces a variety of topics, and the examination of its relation 

 to others introduces many more subjects. 



Morphology is the science of form and structure. Under this 

 head are studied the forms of plant bodies and the portions of 

 which they are composed. All plants except the very simplest 

 are made up of parts, called organs, which are structures devel- 

 oped for particular kinds of work. Thus the stems, roots, and 

 leaves are organs, and so are also the parts of a flower. Morphol- 

 ogy establishes the relationships of organs which seem at first 

 glance very dissimilar, as when leaves take the form of bud scales 

 or . spines or tendrils. Morphology traces the degeneration of 

 parts which frequently cease to perform the work for which 

 "they were originally developed and become much simplified in 

 structure or almost disappear. Thus the tendrils of the wood- 

 bine are shown to be morphologically branches reduced to mere 

 organs of attachment. Although morphology deals with the 

 plant with less regard to its character as a living being, it 

 should never be entirely separated from physiology, but should 

 go hand in hand with that sister subject, equally necessary to 



an understanding of plant life. 



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