1026 EXPERIMENT STATION RECORD. 



starch, and sugar. The acids ave partially transformed into carbohy- 

 drates. This is shown by the culture experiments with the mold and 

 also from the fact that the amount of sugar found in the ripe fruit 

 equals the starch and acids lost. The tannins are completely destroyed 

 by oxidation, there being- no evidence to show that it adds to the carbo- 

 hydrate content of the well ripened fruit. The starch is transformed 

 into sugar, as may be seen by comparing the relative amounts of the 

 two carbohydrates from time to time during maturation. The sugars 

 depend, as has already been shown, upon the starch and acids and 

 in those fruits in which the fermentation quotient continues after 

 maturity part of the sugar is transformed into alcohol, volatile acids, 

 and perfumes. 



The following practical deductions are drawn from the experiments: 

 As acids and tannins disappear rapidly at high temperatures it is pos- 

 sible to hasten the ripening of apples, grapes, oranges, Japanese per- 

 simmons, sorbus, medlars, pears, etc., by exposing them to higher 

 temperatures. The maturity of some apples, grapes, cherries, oranges, 

 etc, may be retarded by cold storage at a temperature of about 0° C. 

 The fruits of the sorbus, medlar, Japanese persimmon, etc., since they 

 continue the fermentation quotient after maturity, can not be preserved 

 for any considerable length of time either at a high or low temperature. 

 The necessity for a high temperature for the transformation of the citric 

 and tartaric acids and the oxidation of malic acid at a low temperature 

 explain how apples, sorbus, medlars, and fruits containing malic acids 

 mature best in cool climates, while grapes and oranges require higher 

 temperatures. They also explain why the fruits of the apple, etc., 

 readily ripen off the tree, while grapes and citrus fruits in general ripen 

 best on the parent plant. The latter fruits maybe ripened successfully 

 off the plant if the temperature be sufficiently increased. 



Respiration of plants at low temperatures, E. Ziegenbein 

 (Natnnr. Wchnschr., 1896, No. 9; abs. in Ann. Agron., 23 {1897), No. 7, 

 pp. 333, 334). — It is stated that Krussler in 1888 showed that cuttings 

 of Kubus, leaves of Phaseoliis vulgaris, Eicinus communis, and Primus 

 lauro-cerasus continued to respire at 0° C. The author shows that car- 

 bon dioxid is liberated by the germination of Lupinus luteus and Triti- 

 cum vulgare at low temperatures. In the ease of the lupine 100 gm. of 

 germinating seed gave oft 5.78 mg. carbon dioxid per hour at —2° O., 

 and 100 gm. of sprouting wheat at 0° liberated 7.90 mg. carbon dioxid 

 per hour. 



The action of alcohol on the germination of fungus spores, 

 P. Lesage (Ann. Sci. Nat. Bot., 8. ser., 3 (1896), pp. 151-159, Jig. 1).— 

 Experiments with Penicillium glaucum and Ster igmatocystis nigra, in 

 which cultures of the spores were suspended in a special form of appa- 

 ratus, show r that alcohol vapors up to concentrations of from G to 8 per 

 cent acting alone do not prevent the germination of the spores. In the 

 presence of watery vapor the limit is raised to about 15 per cent. 

 Beyond these limits alcoholic solutions retard germination, and, if con- 



