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NATURAL FERTILISATION AND CROSS-BREEDING. 



RECENT OBSERVATIONS ON THE FERTILISATION OF PLANTS.* 



IT is proposed in the following section to give an account of 

 some of the most recent observations on the subject of the 

 contrivances by which the fertilisation of flowers is effected ; a 

 subject the details of which are so numerous and varied that 

 the field of observation open, not only to the scientific botanist, 

 but even to the ordinary observer, seems almost boundless. 

 So much has now been written on this subject, that every one 

 who has followed it to any extent is aware that the greater num- 

 ber of flowers are cross-fertilised though to this rule there are 

 exceptions, to which we shall allude presently and that the 

 mode in which this cross-fertilisation is usually effected is by the 

 agency of insects. There are, however, a considerable number 

 of flowers which are fertilised without the assistance of insects, 

 by means of the wind ; and as these present, as a class, peculiar 

 features of their own, we may spend a little time in the first 

 place in considering them. 



The Agency of the Wind. 



A familiar example of flowers fertilised in this way is fur- 

 nished by the common Hazel, which flowers from January till 

 the early part of March, even when the weather is very cold, 

 and when there are scarcely any insects on the wing. The 

 flowers of the Hazel are of two kinds, male and female. The 

 male flowers constitute the familiar catkins, which drop off and 

 disappear before the leaves make their apearance. The cat- 

 kins are generally in bunches of from two to four, every catkin 

 containing on an average perhaps from 100 to 120 flowers. 

 Each of these male flowers consists of a simple scale-like bract 

 enclosing from eight to twelve anthers, each of which dis- 



* By A. W. Bennet, M.A., in the 'Popular Science Review.' Re- 

 printed by permission of the author. 



