Ca&r. X. ANEMOPHILOHS PLANTS. 401 



is fertilised with pollen which is more efficient than 

 that applied to the other flowers on the same peduncle, 

 the latter often drop off ; and it is probable that this 

 would occur with many of the self-fertilised flowers 

 on a large tree, if other and adjoining flowers were 

 cross-fertilised. Of the flowers annually produced 

 by a great tree, it is almost certain that a large 

 number would be self-fertilised ; and if we assume 

 that the tree produced only 500 flowers, and that this 

 number of seeds were requisite to keep up the stock, 

 so that at least one seedling should hereafter struggle 

 to maturity, then a large proportion of the seedlings 

 would necessarily be derived from self-fertilised seeds. 

 But if the tree annually produced 50,000 flowers, of 

 which the self-fertilised dropped off without yielding 

 seeds, then the cross-fertilised flowers might yield 

 seeds in sufficient number to keep up the stock, and 

 most of the seedlings would be vigorous from being 

 the product of a cross between distinct individuals. 

 In this manner the production of a vast number of 

 flowers, besides serving to entice numerous insects and 

 to compensate for the accidental destruction of many 

 flowers by spring-frosts or otherwise, would be a very 

 great advantage to the species ; and when we behold 

 our orchard-trees covered with a white sheet of bloom 

 in the spring, we should not falsely accuse nature of 

 wasteful expenditure, though comparatively little fruit 

 is produced in the autumn. 



Anemopliilous Plants. The nature and relations of 

 plants which are fertilised . by the wind have been 

 admirably discussed by Delpino* and H. Miiller ; and 



* Delpino, 'Ult. Osservazioni naggio anemofilo,' &c. 1871. IT. 

 Bulla Dicogamia,' part ii. fasc. i. Miiller, 'Die Befruchtung,' &c. 

 J870; and 'Studi sopra un Lig- pp. 412, 442. Both these authors 



2 D 



