Mat 28, 1915] 



SCIENCE 



775 



whieli coffee culture was possible. The im- 

 munity of this variety, however, proved to 

 be of an unstable nature, and as a conse- 

 quence the growers were obliged to import 

 C. rohusta, a species having lower commer- 

 cial value, from the virgin forests of Africa. 

 Because of the fact that C. liherica pro- 

 duces beans of much poorer quality than 

 C. arabica and C. roiivsta beans of a poorer 

 quality than C. liherica their substitution 

 was of restricted value, but it saved the 

 valuable coffee industry in some regions 

 from ruin. 



The maintenance of profits with the infe- 

 rior coffee is made easier by the degenera- 

 tion of taste among civilized people — ^the 

 result of standardization in all branches of 

 life. The average man to-day lacks the 

 faculty of determining whether his beef 

 was cut from a Holstein or a Hereford, 

 whether the fowl on his table was fed with 

 barley or oats, whether a wine is natural or 

 sugared, or whether the coffee he drinks is 

 C. arabica, C. liherica or C. rohusta. 



Even though the value of the resistant 

 plant is lower, as in the case of the ex- 

 amples cited, the possibility of improving 

 the variety still remains. Two methods 

 may be used toward this end, that is graft- 

 ing a non-resistant on a resistant variety 

 or crossing the two. The first was fol- 

 lowed in dealing with Phylloxera of the 

 vine in Europe. The European vineyard- 

 ists grafted their own highly cultivated 

 varieties on the roots of the American vine, 

 which latter resists the attacks of the par- 

 asite, and in this way produced a vine com- 

 bining the requisite wine-producing quali- 

 ties of the European vine with the disease 

 resistance of the American vine. In view 

 of these facts it would seem easier to re- 

 place the European vine with the Ameri- 

 can, but this is not practicable, because 

 under European conditions of climate it 

 is not possible to prepare wine from Amer- 



ican species. The grafted vine is only an 

 imperfect substitute, because its life is of 

 short duration and the labor of grafting 

 makes its culture expensive. 



As the grafted vines are heavy bearers, 

 the disadvantages from their use are not 

 felt as keenly in France, where the aim of 

 the vitieulturist is to produce large quan- 

 tities of wine, as in Germany, which aims 

 to produce "quality wines." The really 

 first-class wines are produced from vines 

 which are permitted to grow only a few 

 grapes, and this, coupled with the fact 

 that the quality of wine improves with the 

 age of the vine, shows that the cultivation 

 of grafted vines is more impracticable in 

 Germany than in France. 



Another method of improving disease- 

 resistant wild species and preparing them 

 for cultivation is illustrated in the case of 

 sugar cane. In the eastern part of Asia 

 this plant, especially the high sugar-pro- 

 ducing varieties, is subject to the so-called 

 sereh disease, the nature of which is stiU 

 unknown. In British India, however, the 

 wild resistant Chunee cane was found, but 

 it had too much fibrous substance to be suit- 

 able for sugar-producing purposes. Sev- 

 eral hundred crosses were made between 

 it, on the one hand, and the Cheribon, on 

 the other. As a result of this crossing, sev- 

 eral hybrids were obtained which produce 

 the maximum amount of sugar and are at 

 the same time resistant to the disease. As 

 sugar cane is propagated by using its veg- 

 etative parts, that is parts of the stem, 

 these qualities can be readily preserved. 

 Notwithstanding these favorable results, 

 however, our experience with sugar cane 

 has proved that its "immunity" is not 

 permanent, but diminishes in the course of 

 cultivation, and the same is true in the 

 ease of the two varieties of coffee men- 

 tioned, the disappearance of immunity in 



