APPLE AND PEAR 51 



the prominence and attractiveness of the tree when in flower. 

 Insects of various kinds flies, bees, and moths visit the flowers, 

 and it is largely by their agency that pollination is effected. 

 Self-pollination, while not entirely prevented, appears to be 

 much less satisfactory than cross-pollination. The stamens and 

 stigmas of the flower of the Apple are mature at the same time, 

 but in the Pear the stigmas are mature for some days before the 

 stamens open, so that self - pollination is rendered less likely. 

 The insects pass from flower to flower, sucking nectar or collecting 

 pollen, and a spell of favourable weather at the time the flowers are 

 opening has its result in efficient pollination, and the consequent 

 development of many fruits. 



The fruits of the Apple and Pear, while differing in shape and 

 details, are constructed on the same plan. The petals have fallen 

 off, but the fruit, which corresponds to the further developed 

 inferior ovary, is borne on the thickened flower-stalk, and crowned 

 with the remains of the calyx and stamens. Its structure is seen 

 if cut across or lengthwise (Plate, Fig. D). The succulent portion 

 within the skin is mainly derived from the further development 

 of the hollow receptacle. The carpels, which are only indistinctly 

 marked off from this, contribute, but their inner walls are distinct, 

 forming the " core " of the apple. Each of the five chambers 

 of this usually encloses two black seeds. The fruit is evidently 

 adapted to be eaten by animals, which would carry the seeds to a 

 distance from the parent tree. In the cultivated varieties the 

 succulent portion has been enlarged and become more palatable 

 than in the wild form, a photograph of the fruits of which is 

 represented on the plate. 



The Hawthorn is a near relative of the Apple and Pear and 

 will repay careful study. Space will not allow of its description, 

 but it may be pointed out that the flowers are constructed on the 

 same general plan. The ovary, however, contains only one carpel, 

 or two or three. The fruit has a succulent outer layer, enclosed 

 in which is a stony core protecting the seeds. The fruits are 

 adapted to be eaten b}^ birds, the stone protecting the seeds when 

 passing through their digestive tracts. The conspicuous inflor- 

 escences of the Hawthorn are represented in the accompanying 

 plate. 



