Griffiths: Hardier Spineless Cactus 



191 



quite widely distributed in collections 

 due to the efforts of the Department and 

 Professor J. C. Ellis, who first found it 

 cultivated by Mexicans in the outskirts 

 of Corpus Christi. There are indica- 

 tions that it has been derived by 

 selection from native forms of southern 

 Texas; but the evidence is not conclu- 

 sive. It is perfectly hardy at Austin, 

 and doubtless is fully as hardy as 

 Op. cacanapa, and possibly as hardy as 

 Op. subarmata. In growth it is not as 

 good as the other two; but it is much 

 more smooth, approaching if not quite 

 equaling in this respect the smoother 

 forms of the Indian-fig group. Another 

 feature is the few spicules on the fruits. 

 On these accounts, the species is quite 

 promising for breeding purposes. 



While these three forms appear to be 

 the most promising, and are the ones 

 upon which the greatest effort is being 

 expended at present, it is not at all 

 impossible that other selections may be 

 made of as great, if not even greater 

 merit. One nearly spineless form re- 

 corded under my collection No. 9087, 

 from Webb County, Texas, is a rapid, 

 very succulent, wavy jointed, compact 

 form, as good as any of the above, were 

 it not for its ^ew spines. It is probably 

 very close to, if not the same as, forms of 

 Opuntia subarmata, mentioned on an- 

 other page. Another selection made 

 last year is a remarkably smooth form 



of Op. bentonii. It is thus far devoid 

 of spines, but has quite prominent 

 spicules. This grows rapidly, but its 

 joints are as thin as those of Op. 

 cacanapa. 



The difference in cold resistance of 

 these forms is not great. They will 

 withstand from 12 to 20° lower tem- 

 peratures than the conventional spine- 

 less ones of today ; and will probably all 

 be hardy throughout the entire pear 

 region of Texas. 



SUMMARY. 



The main problem associated with 

 spineless prickly pear culture today is to 

 increase the resistance of these plants 

 to low temperatures. 



Hardy native species of the United 

 States, more particularly of central 

 Texas, are thought to be the most 

 promising source of hardiness. 



Three, with a possible additional two, 

 selections have been made from the 

 Texas region which are considered very 

 promising, and which have been success- 

 fully crossed with the tender spineless 

 species. 



The selections already made have 

 resulted in the production of forms of 

 native hardy species which are entirely 

 devoid of spines, and which remain 

 spineless under cultivation. These 

 forms are also as rapid of growth as the 

 spiny natives of the Texas region. 



Bud Selection Fails 



Bud selection from high producing and low producing strawberries carried on 

 through twelve years showed absolutely no gain in productiveness by selecting 

 runners from high producing parents, at the Missouri agricultural experiment 

 station. 



Raspberry Breeding 



In the work of raspberry breeding at the New York vState agricultural experi- 

 ment station (Geneva), it is reported that "two series of crosses involving over 

 700 seedlings have proved 'Rubus neglecHis' to be a hybrid between R. strigosus 

 and R. occidentalis . At the same time some very interesting white fruited seedlings 

 have appeared and also a seeming mutation, a dwarf, which appears to indicate 

 from its numbers that certain of our raspberries carry dwarfness as a recessive 

 character. Although the crossing of the named varieties has proved unusually 

 successful, much of the future work with both Rubus and Ribes will be in hybridiz- 

 ing species. Already some interesting hybrids have been secured between Ribes 

 nigrum and Ribes oxyacanthoides. To further this hybridization work the station 

 is making a collection of species of these two genera." 



