THE PKAR HARVEST. 211 



the plum tribe. There the solitary seed or stone, witii 

 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, to that the latter forms the edible portion of the 

 so-called fruit. Indeed, it is difficult to examine a pear 

 without observing that the fleshy part really consists of a 

 mere expansion of the stalk, with its fibres gradually 

 lost in a mass of sweet succulent tissue. This change 

 has been very curiously brought about by the sinking of 

 the seed-vessels into the body of the stalk, a singular 

 plan for ensuring safer fertilisation on the visits of bees. 

 The same device is found throughout all the allied 

 members of the rose family, such as the true roses, the 

 hawthorn, and the medlar ; but nowhere in such perfec- 

 tion as among the narrower pear and apple group. It 

 has nothing in common with the method adopted by 

 the strawberry, where the common bed of the numerous 

 seed-cells assumes a succulent condition ; nor with that 

 adopted by the raspberry and blackberry, where the 

 outer coat of each seed-vessel becomes itself a juicy 

 covering ; nor with that adopted by the plum and cherry, 

 which is identical with the raspberry type, save that the 

 number of pulpy seed-vessels to each blossom is reduced 

 to one only. The immense variety of plans by which 

 nature thus secures the same end — the dispersion of the 

 seed by birds or mammals — shows us that whatever 

 may be the character of the useful tendency, it will be 

 equally encouraged and selected by survival of the fittest, 

 irrespective of its conformity to or divergence from any 



fanciful ideal type. 



p 2 



