SECTION 8.] MODIFICATIONS OF THE TYPE. 



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§ 4. MODIFICATIONS OF THE TYPE. 



248. The Deviations, as they may be called, from the assumed type or 

 pattern of flower are most various aud extensive. The differences between 

 one species and another of the same genus are comparatively insignificant; 

 those between different genera are more striking; those between different 

 families aud classes of plants more and more profound. They represent 

 different adaptations to conditions or modes of life, some of which have 

 obvious or probable utilities, although others are beyond particular expla- 

 nation. The principal modifications may be conveniently classified. First 

 those wliich in place of perfect (otherwise called hermajihrodUe or bisexual) 

 flowers, give origin to 



249. Unisexual, or Separated, or Diclinous Flowers, imperfect flow- 

 ers, as they have been called in contradistinction to perfect flowers ; but that 



230 



term is too ambiguous. In 



these some flowers waut the ^^ 



stamens, while others waut the pistils. Taking 

 hermaphrodite flowers as the pattern, it is natural 

 to say that the missing organs are suppressed. This 

 expression is justified by the very numerous cases 

 in which tlie missing parts are abortive, that is, 

 are represented by rudiments or vestiges, which 

 serve to exemplify the plan, although useless as 

 to office. Unisexual flowers are 



Monoecious (or Monoirmis, i. e. of one household), when flowers of boll: 

 sorts or sexes are produced by the same individual plant, as in the Ricinus 

 or Castor-oil Plant, Fig. 230. 



Dioecious (or Dioirous. i. e. of separate households), when the two knids 

 are borne on different plants; as in Willows, Foplars, Hemp, and Moon- 

 seed, Fig. 231, 232. 



Poli/gamous, when the flowers are some of them perfect, and some 



staminate or pistillaie only. 



Fig. 230. Unisexual flowers of Castor-oil plant : s, staminate flower ; p, pistillate 

 flower. 



Fig. 231, staminate, and 232, \.istillate flower of Moonseed. 



