EARLY SUMMER FLOWERS 



191 



the corolla is the large pistil. This consists of the green ovary sur- 

 mounted by five white stigmas, which are receptive to pollen on 

 their inner faces. The ovary, as in the Ragged Robin, has a single 

 cavity, and the ovules are borne on a central projection from the 

 base. The position of the partitions, which are not developed, 

 is indicated by ridges projecting from the inner surface of the wall 

 of the ovary. At the base of the ovary are ten little pointed 

 bodies. There are the rudiments of the stamens, which are here 

 arrested at an early stage of their development. The nectar in 

 this flower is secreted around the base of the ovary. 



In contrast to the Ragged Robin, the Red Campion has flowers 

 of two kinds, pis- 

 tillate and stamin- 

 ate, on distinct 

 individual plants. 

 Comparison with 

 related plants leaves 

 no doubt that this 

 has come about by 

 the arrest of the 

 stamens in the 

 flowers of some 

 plants and of the 

 pistil in those of 

 other individuals, 

 though we know nothing of the cause of this difference between 

 the individual plants. Evidently self-pollination is impossible in 

 the Red Campion, but the long-tongued insects, especially butter- 

 flies, which come to the flowers in search of the deeply placed 

 nectar, will carry pollen from the male or staminate flowers to 

 the stigmas of the female or pistillate flowers. The fruit which 

 develops from the ovary of the pistillate flower is of similar con- 

 struction to that of the Ragged Robin. 



While in the Ragged Robin we have flowers with both stamens 

 and pistil, the development of the stamens before the stigmas 

 were mature almost prevented self-pollination. The separation of 

 the two sexes on distinct plants, as in the Red Campion, renders 

 self-pollination impossible. 



A B 



FIG. 87. Flowers of the Red Campion cut through length- 



wise. A, staminate flower ; B, pistillate flower. 

 Baillon.) 



(After 



