94 



The Plant World. 



to bring this hybrid to maturity, and two or three years more 

 to bring the seedlings of the second generation to a stage suffi- 

 ciently advanced to justify selection. One is then ready, pro- 

 vided no accidents have happened and the species which he has 

 selected will hybridize, to begin selection. The slight variation 

 that occurs in vegetative propagation renders this method of 

 improvement practically useless. The method of improvement 

 by seed selection requires several generations of plants; but when 

 it is remembered that cacti can be grown from seed only with 

 difficulty and that several years are required to grow a generation 

 to the stage of seed production, the magnitude of the task of 

 improving cacti is easily seen. It must be remembered that 

 neither cf the parents is really spineless, even the so-called "spine- 

 less" one having some spines and a strong tendency to revert to 

 a more spiny condition. It takes a long time to breed the spines 

 off entirely, or even practically, but to produce a hardy rapid- 

 growing plant should not be so difficult, provided one's conception 

 of hardiness is not too exacting. The prediction is ventured 

 that if any improvement is made in the hardiness of rapid-grow- 

 ing varieties it will be through the spiny plants and not the 

 spineless ones. 



The main work which the Bureau of Plant Industry will under- 

 take with spineless species during the next two or three years 

 is to test varieties which are now being propagated. Vastly 

 more knowledge is necessary regarding these before anyone will 

 be in a position to inaugurate breeding operations. 



Spineless Cacti in the newspapers are still much in evidence. 

 With apologies to those who believe in " things as they are," 

 the following bit of applied science "as she is wrote" up for the 

 trade is presented. 



SPINELESS CACTUS EXPERIMENTAL CULTURE. 



Specimen Plants to be Sent Out. 



To secure an immediate widespread test cf the value of the THORN- 

 LESS CACTUS as a Fodder Plant. 



The Demand will Exceed the Supply. 



Therefore if you are interested don't waste your own and our time 

 i riting us. Send your Order and a Dollar at once. The published 

 "Field Trial Reports" will be mailed free. 



Only Cue Plant to a Person. 



And then only to those who agree to report the soil conditions, cli- 

 mate and results in pounds for the first year's growth. 



