130 BIOLOGICAL PROBLEMS 



have to recognize something akin to " habit races " in 

 the higher plants, for I think that, as our study of 

 grass-land becomes more thorough, we shall find that 

 local indigenous varieties exist varieties that defy 

 morphological separation unless, indeed, a syste- 

 matic study of minute differences in internal mor- 

 phology may reveal characters capable of recognition. 

 It is evident, at all events, that certain species are 

 locally strongly indigenous, and that these varieties 

 are endowed with properties that make them far more 

 successful colonizers each in its own special locality 

 than are the plants from seeds obtained from the 

 ordinary commercial sources. 



The foregoing considerations open up a wide and, 

 in this country, an almost totally unexplored field for 

 research, namely, the building up of persistent indi- 

 genous and withal productive herbage plants. The 

 problem is more involved than is that of selecting or 

 breeding arable-land plants, for in that case we are 

 at most concerned with biennials, and but few crops 

 are in agriculture treated as biennials. Adverse 

 climatic conditions can be got over to a large extent 

 in the case of annuals, or functioning annuals, by 

 producing rapidly- maturing strains which complete 

 their life-circle during the period of most favourable 

 conditions. Thus, when perfecting wheat, mangels, 

 or sugar beet, you may intensify the characters you 

 desire, and, without knowing it, carry along deficien- 

 cies which would make your new variety incapable of 

 surviving had it to reproduce or maintain itself under 

 conditions of competition such as our four-year-per- 

 sisting herbage plants most successfully contend with. 



It is probable, therefore, that the first step to be 

 taken in building up improved strains of herbage 

 plants is a detailed study of indigenous species from 

 an essentially local standpoint; the essence of the 



