SOME PLANT BIOGRAPHIES. 189 



phyll in the cells just at first both from chilly 

 winds and from the injurious effect of excessive 

 sunlight. Year after year the beech-tree grows 

 by so subdividing and adding branch to branch ; 

 while its stem increases by yearly rings of growth, 

 till it attains at length considerable dimensions. 



During many such seasons of growth the 

 beech-tree does not flower; all the material it 

 manufactures through the summer in its large 

 flat leaves it lays by in its stem to supply the 

 young shoots and branches at the beginning of 

 the subsequent season. But at last, when it has 

 reached the height and girth of a small tree, it 

 begins to store up protoplasm and starches for 

 blossom also. Some of its buds are now leaf- 

 buds, but some are flower-buds, produced in 

 autumn, and held over till April. In the spring 

 these flower-buds lengthen and produce bunches 

 of blossoms, which we call catkins, some of them 

 males, and some females, but both sexes growing 

 on the same tree together. They bloom, like 

 most other catkins, in the early spring, while the 

 leaves are still very little developed, so as to pre- 

 vent the foliage from interfering with the carriage 

 of the pollen. The males are produced in hang- 

 ing clusters an inch or so long; while the females 

 stand up in small globular bunches, on erect 

 flower -stems. They are wind - fertilised ; and 

 shortly after flowering, the male catkins drop 

 off entire, having done their life-work, while the 

 females swell out into the familiar husks or four- 

 valved cups, containing each some two or three 

 triangular nuts, richly stored with food-stuffs. 



The agave only flowers once, and then dies 

 down, exhausted. But the beech goes on flower- 

 ing for many years together, and grows mean- 



