WATER-STRESS BEHAVIOR OF PIMA COTTON. 23 
tions to set more than half of their total number of bolls during the 
first half of the flowering season. 
The data indicate that effort should be made to stimulate the set- 
ting of fruit to the fullest extent during the months of July and 
August, especially in areas frequently visited by comparatively early 
frosts, since the number of bolls set during this period largely de- 
termines the extent of the crop. 
There are indications that an internal physiological reaction re- 
sults from prolonged water stress in the plant tissues which tends to 
inhibit their response and recovery when more favorable conditions 
are restored during later development. 
LITERATURE CITED. 
(1) Allard, II. A. 
[1909]. Notes on cotton breeding in northern Georgia. In Proc. Amer. 
Breeders' Assoc, v. 5, p. 119-130, 6 fig. 
(2) Appleman, Chaeles O. 
1914. Biochemical and physiological study of the rest period in the 
tubers of Solanum tuberosum. Md. Agr. Exp. Sta. Bui. 183, 
p. 181-226, IS fig. Literature cited, p. 225-226. 
(3) Balls, W. Lawrence. 
1912. The Cotton Plant in Egypt. Studies in Physiology and Genetics, 
xvi, 202 p., 72 fig. London. Bibliography, p. 181-190. 
(4) 1915. The Development and Proerties of Raw Cotton, xii. 221 p., 
16 pi., 20 fig. London. List of references, p. 211-214. 
(5) Barre, H. W. 
1915. Report of the botanist and plant pathologist. In S. C. Exp. Sta. 
28th Ann. Kept., 1914-15, p. 21-26. 
(6) Blair, R. E. 
1918. The work of the Yuma Reclamation Project Experiment Farm 
in 1916. U. S. Dept. Agr., Bur. Plant Indus., West. Irrig. Agr. 
Circ. 20, 40 p., 12 fig. 
(7) 1918. The work of the Yuma Reclamation Project Experiment Farm 
in 1917. U. S. Dept. Agr., Bur. Plant Indus., West. Irrig. Agr. 
Circ. 25, 45 p., 16 fig. 
(8) 1920. The work of the Yuma Reclamation Project Experiment Farm 
in 1989. U. S. Dept. Agr. Circ. 75, 77 p., 32 fig. 
(9) Beiggs, Lyman J., and Shantz, H. L. 
1912. The wilting coefficient for different plants and its indirect deter- 
mination. U. S. Dept. Agr., Bur. Plant Indus. Bui. 230, 83 p., 
2 pi., 9 fig. 
(10) 1913. The water requirement of plants. I. Investigations in the Great 
Plains in 1910 and 1911. U. S. Dept. Agr., Bur. Plant Indus.- 
Bui. 284. 49 p., 11 pi., 2 fig. Literature cited, p. 49. 
(11) Coit, J. Eliot, and Hodgson, Robert W. 
1919. An investigation of the abnormal shedding of young fruits of 
the Washington Navel orange. In Univ. Cal. Pub. Agr. Sci., 
v. 3, no. 11, p. 283-368, pi. 25-42, 9 fig. 
