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ration takes place during sunshine. This fact is often dem- 

 onstrated by young cucumber plants in tolerably good health, 

 which not infrequently show some indications of wilt in sun- 

 shine, though not enough to cause any appreciable harm. This is 

 especially so when they are forced too rapidly, and when the texture 

 of the leaf is not sufficiently developed. The temperature of the air 

 affects transpiration. A plant in an atmosphere saturated with moist- 

 ure will not exhale any watery vapor, provided that the temperature 

 of the plant is not higher than that of the air ; but when the temper- 

 ature of the air is high, and the proportion of moisture small, trans- 

 piration is promoted. Transpiration is further affected by the tem- 

 perature of the soil in which the roots are embedded. When the 

 roots are warmed, transpiration becomes more active, and there exists 

 more root absorptive activity. The nature of liquids which the 

 roots absorb and the kind of soil in which they grow also affect 

 transpiration. Plants transpire more when grown in clay than when 

 grown in sandy soil ; also when grown in acid soil than when grown 

 in alkaline soil. Potassium nitrate and other salts diminish trans- 

 piration, and we have been able to produce severe cases of the wilt 

 by watering pots of cucumber plants with a solution of potassium 

 nitrate. 



The methods of growing cucumbers where the wilt occurs are 

 radically wrong in many ways. The houses are imperfectly equipped 

 for ventilation, consequently little use can be made of this necessary 

 feature. Then, again, they are frequently constructed with two 

 layers of glass, which are set about two inches apart, thus leaving 

 an air space between for the purpose of keeping out the cold, but 

 which in reality becomes filled up with dirt, and is an excellent aid 

 in shutting out the light. Plants started in such a house in winter 

 continually suffer from lack of light, — a feature which we have often 

 observed in the greenhouses in this State. Their leaves become 

 pale, their petioles are elongated and slender, and they present all 

 the characteristics of partial etiolation, or, in other words, they 

 resemble plants grown in the dark. If we add to such conditions 

 an enormously high temperature, without proper ventilation, we have 

 a crop that is so tender and abnormally matured that it is incapable 

 of standing strong sunlight. If such a crop is carried over until 

 spring, and subjected to the more intense rays of the sun, the tender, 

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