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TEXTBOOK OF BOTANY 



primordia likewise begin as separate mounds of tissue, but nine of them 

 soon become united at their bases, leaving the tenth stamen primordium 

 free. Fusions of floral parts are common and of great variety, as may be 

 seen if numerous flowers are examined. 



In many flowers, such as those of apple, there is a floral cup composed 

 of the united bases of sepals, petals, and stamens. This floral cup may 



calyx and stamens 



tissue developed . 

 J from the floral cup 

 inner cartilaginous 

 tissue of- ttie o/ulary 

 outer soft tissue 

 of the ovulary 



Fig. 154. Flower, fruit, and seeds of apple. A-D, vertical sections through 

 flowers of different ages. In C, which is about 2.5 natural size, all the parts of 

 the flower have been drawn. The tissues of the ovulary and the floral cup are 

 united. A and B are about 9 times natural size and were made before the flower 

 buds opened. C and D are about 2.5 natural size and were made soon after 

 the petals abscised. E, cross section of a young fruit in which the five carpels 

 and ten of the ovules are evident; F and G, cross and longitudinal sections of a 

 mature fruit, about one-half natural size. 



partially or completely enclose the ovulary and become united with it. 

 The upper parts of the stamens and the lobes of the calyx and corolla 

 appear to be attached to the rim of the cup (Fig. 154). Furthermore, 

 while the ovulary develops as the core of the apple, the floral cup grows 

 and becomes the edible part of the fruit. 



