The Making of Species 
“The method of the clovers and trefoils is quite 
different. When circumstances are favourable 
and enemies few, they will form large-leaved 
luxuriant clumps, with fine heads of blossom; 
but where grazing animals abound they have 
the power of adapting themselves to altered 
circumstances. They creep so closely along the 
ground that the teeth of the grazing animal can- 
not pick them up between the surrounding grass, 
and they produce leaves so small and _ short- 
stalked that to eat them would be like nibbling 
the pile off velvet. Any clover or trefoil thus 
growing in self-defence is accepted as the 
‘shamrock’ of Ireland; and it is certainly a 
fine emblem for a race which regards itself 
as surviving in spite of incessant oppression. 
“These are the reasons, however, why the 
grasses and clovers or trefoils continue to enrich 
old pastures when most of the other plants dis- 
appear, with the exception of daisies and butter- 
cups, and the acid sorrels.” 
We should be glad to hear how Mr Robinson 
accounts for the conspicuous flowers in the 
species of “prickly pear” (Zuphorbza), which is 
so abundant in India, and which is not browsed 
upon by animals. 
We regret that we are not able to devote more 
space to this most interesting theory. We can 
only add that, even if it fail to become widely 
accepted, it is of great value as showing that it 
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