204 COLIN CLOUT'S CALENDAR. 



sli^ditly woody underground stocks, sending forth fresh 

 flowering stems with each returning spring, to small 

 tough under-shrubs whose branches alone die down in 

 autumn, and finally to arborescent bushes, all of whose 

 stiffer boughs become permanently woody from the very 

 first. And side by side with this upward evolution from 

 the green weed to the solid tree we can trace a con- 

 comitant evolution from the many-seeded berr)' like the 

 raspberry or the blackberry to the one-seeded stone- 

 fruit like the sloe and the plum. All those members of 

 the rose family which have reached this highest type of 

 rose development, with shrubby or tree-like stems and 

 one-.seeded fruits, form together the almond sub-tribe of 

 modern botanists. As in all other cases, their succulent 

 fruit-coverings arc due to the selective agency of birds 

 and forestine animals, which aid them in dispersing 

 their large, hard, indigestible seeds ; and the unusual 

 size of these coverings shows at once that they belong 

 as a class to sub-tropical and tropical regions, being 

 adapted to large and active animal allies, as our Eng- 

 lish wild strawberries, raspberries, and blackberries are 

 adapted to the smaller needs of northern birds. 



Even among the plum or almond sub-tribe itself 

 there are many differences of size and colour in the 

 fruit, according to the special localities where the 

 \arious trees have fixed their home. Our little black 

 English bird-cherry is a northern and Arctic variety ; it 

 flourishes best in Lapland and Scandinavia, becomes 

 scarcer and scarcer as we move down into Scotland 

 and central Europe, disappears altogether in southern 

 England and Ireland, and only penetrates into the south 

 European and south Asiatic regions along the snowy 



