628 EXPERIMENT STATION RECORD. 



CEnothera. Eichbornia possessed the largest dayligbt openings, followed by 

 Allium and OEnotbera. 



A comparison of the amount and rate of stomatal closure, as exhibited by 

 the 2 sides of the leaf, indicates that the upper stoniata close and open more 

 rapidly, or close more completely, than do the lower, although this difference 

 is not prououucetl in Eichbornia. 



The respiration of fungi, A. Maige (Bui. Soc. Hist. Nat. Afriqiie Nord, J 909, 

 No. 2, pp. 29-31). — From observations made upon a number of the fleshy fungi, 

 the author concludes that respiration is much more active in the reproductive 

 than in the vegetative portion of the fungus. This is particularly true of 

 Armillaria mcllea, in which the respiration of the cap was 3 times as great as 

 that of the stalk. 



The comparative influence of some organic substances on respiration, 

 A. Maige and G. Nicolas (BuL 8oc. Hist. Nat. Afrique Nord, 1910, No. 5, pp. 

 71-81). — The effect of saccharose, lactose, and glycerin on the respiration of 

 etiolated shoots of beans was investigated. It was found that in general the 

 influence of organic substances on the respiration of plants depends on 3 factors, 

 the ability to penetrate to the interior of the cells, the retardation of cellular 

 growth due to osmotic pressure, and the specific quality of the different sub- 

 stances. 



The variation in the respiration of plants in proportion to ag'e, G. Nicolas 

 (Bui. Soc. Hist. Nat. Afrique Nord, 1910, No. 7, pp. 109-112).— A study of 

 young and adult leaves of about 20 species of plants was made, and it was 

 found that the young leaves presented in comparison to those fully develoi>ed 

 a greater respiratory energy and a higher respiratory quotient. This difference 

 in the respiration to a large degree is due to the greater ease of penetration of 

 the gas to the young leaves. 



The wilting coefiicient for diffei-ent plants and its indirect determination, 

 L. J. Briggs and H. L. Shantz (U. 8. Dept. Agr., Bur. Plant Indus. Bui. 230, 

 pp. 83, pis. 2, figs. 9; Bot. Gaz., 53 {1912), No. 1, pp. 20-37; ahs. in Science, n. 

 scr., 35 (1912), No. 891, pp. 158, 159). — A study was made to determine whether 

 the wilting coefficient of a soil could be computed from physical measurements 

 of its moisture retentivity. The experiments reported were conducted with a 

 variety of plants, in which a comparison of the wilting coefiicient was made 

 with the moisture equivalent, the hygroscopic coefficient, the moisture-holding 

 capacity, and the mechanical analysis, for a series of soils ranging from pure 

 sand to clay. 



From this comparison a series of relationships was established which form g 



means of computing the wilting coefficients when direct determinations are not 



feasible. The authors found that the wilting coefficient was equal to 



moisture equivalent . hygi-08Copic coefBcient . moisture-holding capacity— 21. 



1.84(1±0.007) ' 0.68(1±0.018) ' 2.90 (1±0.021) ' ^^ 



0.01 sand + 0.12 silt -f 0.57 clay ^, , ^ „ ^, ,.^ -.u- ^v. 

 ri^002^^ '' second term of the quantity withm the 



parenthesis is believed to show the probable error of the relationship in 

 each case. 



On page 77 in the bulletin the last formula for wilting coefficient should 

 have the signs in the numerator plus ( + ) instead of minus ( — ). 



A study of summer evaporation and plant distribution, B. E. Livingston 

 {Plant World, 14 {1911), No. 9, pp. 205-222, figs. 3).— The results are given of 

 a study of the evaporation from iwrous cup atmometers at 38 stations in the 

 United States and Canada, covering a period of 15 weeks during the summer. 

 The author claims that the summer evaporation intensity furnishes a climatic 

 criterion for studying the different vegetation centers, and that the results of 



