CHAPTER IX 



THE THORNLESS EDIBLE CACTUS 



problems which confront Mr. Bur- 

 bank in his work are many and some- 

 times of great difficulty. One plant may 

 present a simple nature and a comparatively 

 short life history. Another may be exceed- 

 ingly complex in nature and of great age. The 

 first he finds easy of manipulation, the second 

 often very difficult. The plants with millions 

 of years back of them, which may be traced in 

 the very rocks themselves, are likely to prove 

 stubborn, to persist in their old habits ; or, if 

 they at first appear to yield, to return to these 

 old habits at a later day. 



He has found this particularly true of the 

 cactus, in the changing of which he has 

 accomplished one of his most wonderful 

 achievements. For years he had had the 

 cactus under consideration. It had long 

 seemed to him that it should be taken out of 

 its environment and set forward among the 



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