378 BULLETIN No. 127. [August, 



i. THE USE OF OTHER SPECIES 



The plant which bears the tuber which we call the potato, and 

 which name has been extended to the whole plant, has a recorded 

 history of only three hundred years, it having been introduced into 

 Europe about the end of the sixteenth century. Its botanical char- 

 acter caused it to be called Solatium tuberosum by Gaspard Bauhin 

 (86) in his Phytopinax, printed at Bale in 1596. This name was 

 followed by Linnaeus when binomial nomenclature was introduced. 



There are several other members of the genus which bear tubers, 

 but none has yet become of commercial importance. About twenty 

 tuber-bearing kinds of Solanum have been at different times classed 

 as separate species. J. G. Baker (6) has given us probably our best 

 classification, after having made a thorough examination of all 

 species at Kew, the British Museum, and the Lindley Herbarium, 

 as well as many growing specimens. He concludes that there are 

 only six distinct species : S. tuberosum Linn., S. Maglia Schlecht, 

 S. Commersonii Dun., S. cardiopJiyllum Lind., S. Jamesii Torr. and 

 S. oxycarpum Schiede. Later, (7) he places S. Maglia as a va- 

 riety of S. tuberosum which reduces the number of species to five. 



Solanum Commersonii Dun. has been shown, by Labergerie 

 (65) to be in all probability the most promising of the other species, 

 in its commercial possibilities. In his extended investigations, it 

 showed a great tendency to produce bud variations in color which 

 were permanent, and which when propagated showed great differ- 

 ences in the production of tubers, immunity to disease, etc. A vio- 

 let variation showed absolute immunity to late blight Phytophthora 

 infestans (Mont.) De By., for three years, while plants of S. tu- 

 berosum growing near were stricken.. The yield was as high as 

 100,000 K. per hectare with a composition much the same as the 

 common potato. Rev. J. R. Lawrence of North Middleboro, Mas- 

 sachusetts, has recently stated, however, that his plants have not 

 been immune to late blight. 



S. Maglia Schlecht. of Chili, S. immite Dun. of Peru, and S. ver- 

 rucosum Schlect. of Mexico, have all been mentioned as species and 

 varieties especially worthy of being tried in the hopes of finding 

 strains which by selection might become of commercial value and 

 be immune to certain diseases, or with which the same end might be 

 reached by hybridization with 5*. tuberosum. No valuable com- 

 mercial strains from these sources, however, have yet been pro- 

 duced. 



Stuart (92) found in 1904 that S. Commersonii and 5. poly- 



