200 COLD* CLOUT'S CALENDAR. 



strength enough meanwhile to enable them to withstand 

 the gale better than their tenderer and later neighbors. 

 Different trees and different varieties show very different 

 degrees of hardihood in this matter ; some kinds of 

 pear, such as the Forelle, will resist frost just after 

 flowering which kills every other sort ; while compara- 

 tively few pippins or improved English varieties of apple 

 can be grown at all in the latitude of Stockholm. In 

 fact, the petty differences upon which natural selection 

 works for the ultimate production of new species exist 

 abundantly everywhere ; and there is hardly any such* 

 difference, however minute, that will not give one 

 variety an advantage over another in some peculiar 

 habitat or situation. 



Fundamentally, of course, apples and pears may be 

 regarded as slightly divergent descendants of the same 

 common ancestor. Our sour little wild crabs and hedge- 

 row pears show us the two types in their earliest diver- 

 gent form, as yet not very widely separated from one an- 

 other ; for their distinctive excellences have been largely 

 brought out by cultivation, which, as in many other 

 cases, has exaggerated their differences of set purpose, so 

 as to produce two fruits in place of one. The rose 

 family, that great mother of succulent fruits, which rises 

 in one direction toward the plums and the peaches, rises 

 in another toward the pears and apples. But the mode 

 in which the fruity effect is here produced greatly differs 

 in principle from the mode in which it is produced 

 among the plum tribe. There the solitary seed or 

 stone, with its pulpy covering, stands out from the calyx 

 as a separate organ in the centre of the flower ; here, on 

 the contrary, the five cells or seed- vessels which make up 

 the core have completely coalesced with the swollen 

 calyx, so that the latter forms the edible portion of the 



