LUTHER BURBANK 



also to be grown with profit even in the most 

 expensive agricultural lands, especially for feed- 

 ing with other forage crops. But in no land will 

 they come upon a cactus from any other region 

 that closely resembles them in their combination of 

 entire spinelessness and inviting forage qualities. 

 PARTIALLY SPINELESS MATERIAL 



Yet it must be understood that the various 

 specimens of cactus that have been sent me from 

 all over the world, many of which were utilized 

 in crossing and hybridizing and selective experi- 

 ments, were often forwarded under the supposi- 

 tion that they were specimens of spineless races. 



And many of them were relatively spineless. 



Some of them showed individual slabs that 

 were almost free from spines. 



But without exception these plants, notwith- 

 standing their relative smoothness, would be found 

 to have inconspicuous spicules or bristles, which 

 constituted an armament almost as offensive as 

 the larger spines; or else would soon demonstrate 

 that their spinelessness was an individual peculi- 

 arity rather than a trait of the race to which they 

 belonged, by developing spines on new slabs. 



Yet the fact that partially thornless Opuntias 

 exist in many regions demonstrates a tendency on 

 the part of this plant to give up its spines partially 

 under some circumstances. 



[196] 



