i;o THE EVOLUTIONIST AT LARGE. 



plum and red in the cherry as the fruits 

 ripen, it remains green and brown in the 

 walnut and coco-nut all their time. Never- 

 theless, Darwinism shows us both here and 

 elsewhere that the popular distinction answers 

 to a real difference of origin and function. 

 When a seed-vessel, whatever its botanical 

 structure, survives by dint of attracting ani- 

 mals, it always acquires a bright-coloured 

 envelope and a sweet pulp ; while it usually 

 possesses a hard seed-shell, and often infuses 

 bitter essences into its kernel. On the other 

 hand, when a seed-vessel survives by es- 

 caping the notice of animals, it generally has 

 a sweet and pleasant kernel, which it pro- 

 tects by a hard shell and an inconspicuous 

 and nauseous envelope. If the kernel itself 

 is bitter, as with the horse-chestnut, the need 

 for disguise and external protection is much 

 lessened. But the best illustration of all is 

 seen in the West Indian cashew-nut, which 

 is what Alice in Wonderland would have 

 called a portmanteau seed-vessel a fruit and 



