50 THE BOOK OF NATURE STUDY 



and stamens all appear to stand upon this. As the section of the 

 flower of the Pear shows (Plate, Fig. B), this is a very instructive 

 inferior ovary to study, for the hollow receptacle can be easily 

 distinguished from the carpels with which it is fused. The calyx 

 consists of five long pointed sepals, which are hairy both on the 

 inner and outer surfaces. When the flower has opened and the 

 protective function of the calyx is over, the sepals bend backwards 

 and lie against the sides of the inferior ovary. The large petals 

 are thin and delicate. They alternate with the sepals, and each 

 has a short, narrow, stalk-like region, expanding into the oval 

 conspicuous part. Within the corolla come the numerous 

 stamens, the anthers of which are red in the Apple, yellow in the 

 Pear. Surrounded by the stamens are the five styles, belonging 

 to the five carpels which form the pistil. The styles are more or 

 less united together below, where they are covered with soft white 

 hairs, but their upper parts are free. Each style ends in a small 

 stigma. 



The surface of the concave disc between the insertion of the 

 stamens and the base of the styles is the nectary, and is best seen 

 when a flower is cut in half lengthwise. Such a section (Plate, 

 Fig. B) also shows well the general relations of the various parts 

 of the flower to one another. The flower-stalk is seen to widen 

 into the hollow floral receptacle which closely surrounds and is 

 united with the carpels to form the inferior ovary. Above this 

 the receptacle continues as a thick rim, the inner sloping lace of 

 which is the nectary, while the sepals, petals, and stamens stand 

 on the edge of the rim. Within the hollow receptacle are the 

 lower portions of the carpels, the upper portions projecting 

 as the styles in the centre of the flower. Within the carpels 

 are the small ovules. Only two carpels will be cut through in 

 this section of the flower, but on cutting the ovary of another 

 flower across and looking at it with a lens five carpels will be 

 seen. These can be more easily studied if the ovaries of flowers 

 which are enlarging in the course of the development of the fruit 

 are taken for examination. 



The flowers of an Apple or Pear tree are very conspicuous. 

 Not only are the individual flowers fairly large, but their associ- 

 ation in inflorescences and the numbers borne on the tree increase 



