34 COLIN CLOUT'S CALENDAR. 



be inclined to imagine : for the majority of spring- 

 flowering trees have their blossoms in those large yet 

 inconspicuous masses which we call catkins ; while 

 others, like the elms, have them in dense clusters, so 

 closely seated on the boughs that comparatively few 

 passers-by notice them. Almost all our larger native 

 trees are catkin-bearers oaks, alders, birches, hazel, 

 beech, sallow, osier, poplar, and aspen ; but only a few 

 of them have catkins which attract much attention, the 

 silvery white knobs of the willow family and a few 

 others being the only ones which most people pick in 

 spring among the woods. None of our own English 

 trees has such a brilliant spring blossom as the flowering- 

 almond, but among southern plants similar masses of 

 early bloom are not uncommon. 



In every case the reason for the flower preceding the 

 leaves seems to be the same. It is in principle a chapter 

 of natural economy, and it illustrates very well the way 

 in which all nature is necessarily compelled to piece in 

 with itself in every part. The catkin-bearing plants are 

 chiefly, if not always, wind-fertilised ; and they have 

 their stamens on one tree and their pistils on another, 

 thus ensuring the highest possible degree of cross-fertili- 

 sation. They produce enormous quantities of pollen, 

 which they require, owing to the distance that often 

 intervenes between one tree and another, and the 

 wasteful nature of the wind as a carrier ; and this pollen 

 falls from tnem as a copious yellow powder when they 

 are placed in a vase on a table, while it can be shaken 

 in great quantities from the trees themselves. If the 

 catkins did hot come out till the branches were all 

 covered with foliage, their chance of fertilisation would 



