MOORLAND PLANTS 213 



stamens. So much pollen is emitted by the small 

 but numerous flowers, that in walking over a patch of 

 Crowberry we kick up clouds of yellow dust. Such 

 abundance of pollen points to wind-fertilisation. Hazel, 

 Grasses, Pines, and other wind-fertilised plants pro- 

 duce immense quantities of pollen, nearly all of which 

 is wasted. Insects, if guided exactly to the right 

 place by the formation of the flower, bring the pollen- 

 grains surely and accurately to the stigma. Economy 

 of this precious dust is the reward of the flowers 

 which are able to win the co-operation of Insects. It 

 is not every clump of Crowberry which yields pollen. 

 About half of the plants bear blackish-purple female 

 flowers instead of stamens. There are also a few 

 flowers with both stamens and pistil. The pistil 

 ripens to a small black fruit, which is harmless and 

 even refreshing when there is nothing larger or better- 

 flavoured to be had. Grouse devour it in large 

 quantities, and thus sow the seeds up and down. 



The leaves of Crowberry are well worth careful 

 examination. They are smooth and glossy. At first 

 sight we should say that they were rather succulent, 

 but on pinching them we find that they are not 

 succulent, only a little inflated. Along the middle of 

 the under surface runs a white line, which we might 

 take for a midrib. But if we examine the leaf with a 

 lens, or better still, slice it across with a razor, we find 

 that the blade is bent round into a hollow cylinder, 

 and that the white line is the meeting-place of the 

 edges. Only one surface of the leaf is exposed, that 

 surface which in ordinary leaves is uppermost. This 

 is smooth and shining in Crowberry, and curves 



