SECTION 8.] MODIFICATIONS OF THE TYPE. 



35 



§ 4. MODIFICATIONS OF THE TYPE. 



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

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

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

 those between different genera are more striking ; those between different 

 families and 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 maybe conveniently classified. First 

 those which in place of perfect (otherwise called hermaphrodite 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 



term is too ambiguous. In 

 these some flowers want the 

 stamens, while others want the pistils. Taking 

 hermaphrodite flowers as the pattern, it is natural 

 to say that the missing organs arc suppressed. This 

 expression is justified by the very numerous cases 

 in which the 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 Monoicous, i. e. of one household), when flowers of both 

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

 or Castor-oil Plant, Fig. 230. 



Dioecious (or Dioicous, i. e. of separate households), when the two kinds 

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

 seed, Fig. 231, 232. 



Polygamous, when the flowers arc some of them perfect, and some 

 staminate or pistillate only. 



Fio. 230. Unisexual flowers of Castor-oil plant : », sUininate flower ; />, pistillate 

 flower. 

 Fio. 281, staminate, and 232, pistillate flower of Moonseed. 



