THE CACTUS 161 



elated. Should their present promise be fulfilled, 

 the giant spineless Opuntias may make vast areas 

 that heretofore have been relatively sterile 

 among the productive regions of the world. 



They may supply fodder for unlimited num- 

 bers of cattle, that will give cheaper food to the 

 masses, and conspicuously decrease the cost of 

 living. 



They may even avert famines in regions that 

 have hitherto accepted the recurrence of starva- 

 tion years as an inevitable visitation. 



And even should the future benefits that ac- 

 crue from the new spineless Opuntias realize 

 but a fraction of their present promise, these 

 plants might still be entitled to a foremost place 

 among the forms of vegetable life that have been 

 introduced, or improved, for the service of man 

 within the historical period. 



THE HEREDITY &F SPINELESSNESS 



Before taking leave of the spineless cactus, 

 it may be of interest to make further inquiry 

 as to the hereditary bearings of the condition of 

 spinelessness. 



We have seen that the new spineless Opuntias 

 were developed by a long series of experiments 

 in hybridizing and selection, in which use was 

 made of individuals that showed a propensity 



6 Vol. 6 Bur. 



