THE CLOVER FAMILY 



chapter^ the grasses are a particularly successful 

 group of plants, although their success is brought 

 about by entirely different means from that em- 

 ployed b)^ the clovers. 



What I have written above applies only to the 

 familiar white or Dutch clover, for the red and 

 purple species do not turn down their flowers as 

 they are fertilised ; indeed, it may be said that 

 each of the twenty or more British species of 

 clovers has its own particular devices in the 

 struggle for existence. The red and purple clovers, 

 therefore, conduct their affairs on quite different 

 principles from the white species. 



There are a few other white and also pink and 

 yellow species which turn down their flowers after 

 fertilisation, just as the Dutch clover does, but 

 even these species differ amongst themselves very 

 considerably in the manner in which they protect 

 their pods while their seeds mature. Sometimes 

 the pod is covered by the calyx, or green outer 

 parts of the flower, which enlarges and develops 

 about it irritating hairs or sharp prickles, thus 

 making the pods unpalatable to sheep, donkeys, 

 and other grazing animals ; in other cases they are 

 considerably hardened for the same purpose ; and, 

 finally, there is the Subterranean Clover (Trifolhnn 

 siihterraneiim) that only bears some two or three 

 flowers in each head, and consequentl}^ has to take 

 great care of its pods. Its method is not to turn 

 down its individual flowers, as the white clover 

 does, but, instead, immediately after fertilisa- 

 tion, the whole head is turned earthwards ; and, 



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