266 THE FLOWER. 



and has therefore been named Salix monandra. But on inspec- 

 tion this seemingly single stamen is found to consist 

 of two united quite to the top (Fig. 330). Here, as in 

 many other cases, the normal condition of the flower is 

 not only much altered by the suppression of some organs, 

 but disguised by the coalescence of those that remain. 

 The blossoms of the Birch are very similar, except that 

 three pistils, the sole representatives of as many flowers, 

 are found under each bract of the fertile catkin. 



474. When the stamens and pistils are thus separated, the two 

 kinds of blossoms may be borne, either upon different points or 

 branches of the same individual, or upon entirely different individ- 

 ual plants. The flowers are said to be monoecious when both kinds 

 are produced by the same individual plant ; as in Indian Corn, the 

 Birch, the Oak, Beech, Hazel, Hickory, &c. : and they are called 

 dicecious when borne by different individuals ; as in the Willow 

 and Poplar, the Sassafras, the Prickly Ash, the Hemp, Hop, &c. 

 In many cases, while some of the flowers are staminate only, and 

 others pistillate only, a portion are perfect, the different kinds oc- 

 curring either on the same or different individuals ; as in most 

 Palms, in many species of Maple, &c. : plants with such flowers 

 are said to be polygamous. 



475. The term suppression in all such cases merely denotes 

 that the parts in question are wholly left out. It is the non-pro- 

 duction of some organ or set of organs which forms a component 

 part of our pattern plan of the flower, and which is realized in the 

 complete flower. The term abortion, which is often used with 

 exactly the same meaning, is more properly applied to those cases 

 where the organ is deformed or imperfect (where a sterile fila- 

 ment, for example, occupies the position of a stamen), or where a 

 mere rudiment marks the place of a non-developed organ. 



476. The suppression or abortion of a whole circle of organs in 

 a symmetrical flower does not destroy its symmetry, if we count 

 the absent members. Thus a monochlamydeous flower, with a 

 single full circle of stamens, usually has the latter placed opposite 

 the leaves of the perianth, that is, of the calyx, the corolla or in- 

 tervening circle, with the members of which it normally alternates, 

 having failed to appear ; as in Comandra (Ord. Santalaceae), Che- 



FIG. 330. A staminate flower of Salix purpurea (or monandra), with the stamens coalescent 

 (monadelphous and syngenesious), so as to appear like a single one. 



