MORPHOLOGY OF ANGIOSPERMS. 



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Fig. 87. Ways in which cross-pollination is effected in some hermaphrodite flowers. 

 I, 2, Flowers of buckwheat, showing long style and short filaments in 1, and short styles 

 and long filaments in 2: a, anthers; st, stigmas; n, nectaries. 3, Spike of plantain showing 

 maturing of stamens below and pistils above. 4, Dissected flower of plantain; b, bract; 

 c, calyx; p, corolla tube; s, stamens; t, protruding withered style. 5, Flowers of Purple 

 willow-herb (Lythrum Salicaria), one side of the perianth removed from each. A is long- 

 styled, B medium-styled, and C short-styled. The direction of the arrows and dotted lines 

 indicates the best methods of crossing. — i, z, 5, adapted from Warming. 



