ON THE SPINELESS CACTUS 



For years collectors in all parts of the world 

 have gathered specimens for me, and as knowledge 

 of my work went abroad, even collectors who 

 knew me only by reputation have sent specimens 

 of one kind or another, until my experiment gar- 

 den may be considered the great gathering place 

 of the varied clans of the cactus family. 



In addition to the specimens received from 

 private collectors, I received also a collection that 

 had been gathered at Washington for botanical 

 classification. Most of these were curious thorny 

 specimens, and I think none of them was used in 

 my successful experiments, although all of them 

 were tested. 



Some of the most important acquisitions were 

 sent by my friend, David C. Fairchild, including 

 slabs gathered in France and Sicily. I received 

 also specimens from Mexico, South America, and 

 Hawaii, as well as almost numberless varieties 

 from all regions of the United States where any 

 form of cactus grows. The so-called Smith Cac- 

 tus, a variety introduced into California by Pro- 

 fessor Emery E. Smith, about forty years ago, 

 proved of value as a hybridizing agent. 



MANY SPECIES, BUT MORE NAMES 



But it is almost impossible to gain a really 

 accurate conception of the materials employed, 

 because of the great confusion of the classifiers, 



[187] 



