144 American Hortieultural Society. 



essay upon the cause and prevention of potato blight — a prize lor which 

 ninety- four eminent scientists contended, but which the committee of 

 awards, appointed by the Royal Society, declared could not be claimed by 

 any of the essnyists, though most of them agreed upon the degenerntion. of the 

 tuber as the great underlying condition for the fungoid attack of the plague 

 {Peronospora infestans), produced by long -continued, improper, unnatural 

 so-called cultivation of the potato by dissection, and by highly stimulating 

 manures. 



Aside from these startling or otherwise interesting facts and these precau- 

 tionary hints, it may be of great financial or economical importance to have 

 new (provided they are better) varieties of potatoes introduced to pcjpular 

 favor at any time. This we propose to do by going at once to original spe- 

 cies, as the Rev. Chauncey E. Goodrich did after the great blight in 1S50, by 

 which he renewed the culture of potatoes, or rather substituted new ones for 

 them, and gave us all we have of potato strains to-day. 



But we shall not select for parent stocks the Aquinas, from the coast of 

 Chili, nor yet the Noaglias, from near the summits of the Peruvian Andes; 

 but we choose the apparently fully as promising species growing almost at 

 our doors in the mountains and high plateaus of the Southwest. 



Without repeating any part of the account of how these potatoes were re- 

 discovered by us, two years ago, we will proceed at once to a description and 

 examination of the two species. They are known to scientists as Solanum 

 tuberosum, Linn., var. boreale, Gray, and Solatium Jamesii, Torr. The first spe- 

 cies was discovered many years ago, on the Rio Grande, near El Paso, by a 

 botanist named August Fendler, and was named then by Dr. Gray S. Fend- 

 leri. Afterwards better specimens convinced the doctor that the plant was 

 but a northern type of the original S. tuberosum, of South America, and so 

 he named it as above, variety boreale. It slightly resembles some varieties 

 under cultivation, as will be seen by herbarium specimens presented to the 

 Society for examination, and also by the accompanying paintings, executed 

 on the ground in water colors. 



This species is ascending in habit, about two feet high or less, with mostly 

 simple stems, lanceolate-oblong leaflets; large purple flowers followed al- 

 most surely by abundant bolls of seed. The tubers are produced upon long, 

 slim, white stolons, and are depressed oval in shape, from one-half to an inch 

 in diameter, and of a purplish color when first exposed to light. It will be 

 noticed that the leaflets of this plant have occasional minute leaflets inter- 

 posed. This character connects closely to cultivated sorts, and is used by 

 the authorities to separate this species from the next, but we have noticed 

 that this feature is common to all, though in varying degrees. 



The second species, Solanum Jamesii, avhs sparingly collected by Dr. James, 

 of Long's exploring expedition to the Rocky Mountains of Colorado, and 

 was named in honor of Dr. James. The plant is usually smaller, with pros- 

 trate branching stems, longer and narrower leaflets (the minute, interposed 

 ones being fewer), a less number of flowers to the umbell, which are white 



