CHAPTER VIII 

 THE MORPHOLOGY AND PHYSIOLOGY OF SEEDS 



1. The Distinctive Characteristics of Seeds 



Seeds form the transportation stage by which plants, 

 otherwise sedentary, are spread outward from their places 

 of origin. They are relatively small parts, which separate 

 of themselves from the parent plants, are so constructed that 

 they may be kept long alive and carried afar, and then 

 when planted, produce individuals like those which produced 

 them. Living under diverse conditions, and transported 

 by various agencies, they differ much in their various ex- 

 ternal features. 



In size, seeds vary from almost dust fine in some tropical 

 Orchids (much smaller than the scriptural mustard seed), 

 all the way up to the Coconuts, the mean or average size 

 lying, however, much nearer the former than the latter 

 dimensions. 



In shape, seeds are most diverse, from approximately 

 globular to elongated, variously angled, and extremely flat, 

 the particular shape being apparently connected in some 

 cases with the method of dissemination, in others with the 

 shape of the embryo, and in others with less evident factors. 

 Often the shape is complicated by the development of 

 special outgrowths, — plumes, hooks, etc., — having con- 

 nection, as in case of fruits, with dissemination. 



In color, seeds are sometimes bright, chiefly red or yellow, 

 as are some fruits, and in other cases are mottled, sometimes 

 in ways which simulate the markings of insects ; and all of 

 these features may have connection with dissemination 



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