224 Flowers and their Pedigrees. 



inclosed in bony cases, but only in those rather tough 

 leathery coverings which form what we call the core. 

 The haw of the hawthorn may be regarded as a very 

 small crab-apple, in which the walls of the seed cells 

 have become very hard and stony ; or the crab may be 

 regarded as a rather large haw, in which the cell walls 

 still remain only thinly cartilaginous. The flowers 

 of all the group are practically identical, except in size, 

 and the only real difference of structure between them 

 is in the degree of hardness attained by the seed covers. 

 The crabs, the apples, and the pears, however, all grow 

 into tallish trees, and so have no need for thorns or 

 prickles, because they are not exposed to the attacks 

 of herbivorous animals. Ordinary orchard apples are, 

 of course, merely cultivated varieties of the common 

 wild crabs. In shape the apple-tree is always spread- 

 ing, like an arboreal hawthorn, only on a larger scale. 

 The pear-tree differs from it in two or three small 

 points, of which the chief are its taller and more 

 pyramidal form, and the curious tapering outline of 

 the fruit. Nevertheless, pear-trees may be found of 

 every size and type, especially in the wild state, from 

 a mere straggling bush, no bigger than a hawthorn, 

 to a handsome towering trunk, not unlike an elm or 

 an alder. 



In the matter of fruits,- the apple group are more 



