SELECTED BIBLIOGRAPHY 213 



24 hour period by the hygrometric paper method and by weighing. The 

 transpiration of a similar tobacco shoot from which the roots had been 

 removed was measured during the same period with a potometer. Plot 

 curves which might reasonably be expected to represent the results of each 

 of these series of determinations on a "standard day" and explain any dif- 

 ferences in the shape of the curves. 



15. The vapor pressure of the atmosphere is often relatively constant upon clear 



summer days. Measurements of the vapor pressure of the air close to 

 plants often show appreciable variations from hour to hour during the 

 day. How may these apparently contradictory facts be explained? 



16. A plant is growing under conditions of constant light, temperature, and 



humidity in a current of air from a fan. The fan is turned off for a few 

 minutes, and the rate of transpiration decreases. If the fan is now started 

 again the rate of transpiration is found to rise to a higher value than just 

 before the fan was turned off. Explain. 



Suggested for Collateral Reading 



Burgerstein, A. Die Transpiration der Pflanzen. I, II, and III. Gustav 



Fischer. Jena. 1904, 1920, 1925. 

 Maximov, N. A. The plant in relation to luater. Edited by R. H. Yapp. 



George Allen and Unwin. London. 1929. 

 Seybold, A. Die physikalische Komponente der pflanzlichen TraTispiration. 



Julius Springer. Berlin. 1929. 



Selected Bibliography 



Anderson, D. B, Relative humidity or vapor pressure deficit. Ecology 17: 



277-282. 1936. 

 Brooks, C, and D. F. Fisher. Some high temperature effects in apples: con- 

 trasts in the tivo sides of an apple. Jour. Agric. Res. 32: 1-16. 1926. 

 Brown, H., and F. Escombe. Researches on some of the physiological processes 



of green leaves, etc. Proc. Roy. See. (London) B. 76: 29-137. I905- 



(4 papers.) 

 Chung, C. H. A study of certain aspects of the phe?iomenon of transpiration 



periodicity. Dissertation Ph. D. Ohio State University. 1935. 

 Curtis, O. F. Leaf temperatures and the cooling of leaves by radiation. 



Plant Physiol, ii: 343-364. 1936a. 

 Curtis, O. F. Comparative effects of altering leaf te?nperatures and air hu- 



Tnidities on vapor pressure gradients. Plant Physiol. 11 : 595-603. 1936b. 

 Day, P. C. Relative humidities and vapor pressures over the United States. 



Mo. Weather Rev. Supplement 6. 191 7- 

 Leighly, J. J note on evaporation. Ecology 18: 180-198. 1937. 

 Martin, E. V. Effect of solar radiation on transpiration of Helianthus annuus. 



Plant Physiol. 10: 341-354. 1935. 

 Martin, E. V., and F. E. Clements. Studies of the effect of artificial ivind on 



growth and transpiration in Helianthus annuus. Plant Physiol. 10: 613- 



660. 1935. 



