1917] FIELD CROPS. 737 



Of the 163 plants which produce flowers after treatment, 29 developefl some 

 flowers of the opposite sex. Four of these plants were males and 25 females. 



It is evident that the sex of hemp is alterable by the removal of flowers. 

 Although only a few male plants produced pistils, they constituted from 14 to 21 

 per cent of the total number of males producing flowers after mutilation, while 

 the females were very responsive to the stimulus of flower removal. In the 

 second year's experiments every female mutilated produced stamens. These 

 results seem to indicate that sex is not wholly a matter of zygotic constitution 

 but that both males and females are potential hermaphrodites, as believed by 

 Darwin and Strasburger. 



Rice variety studies, E. van Drent (Dept. Landh. Suriname Verslap, 1915, 

 pp. 62-66). — This is a brief account of some rice variety trials, including a 

 study of the plat arrangement employed. Each of the five varieties tested were 

 .sown in three parallel plats, the planting distances being 0.5, 1, and 1.5 ft., 

 respectively. Brief notes are given on the cultural characteristics of each 

 variety with special reference to their resistance to wind. No conclusions as 

 to the best distance for planting could be drawn, but the experiments will be 

 continued in 1916 with two varieties, using the same system of plats, and 

 from these it is hoped to obtain definite results. 



[Sugar cane] {Hawaii. Sugar Planters' Sta. Proc, S5 {1915), pp. 20-26, 

 64-80, 86-113). — Progress in variety testing at the Waipio substation and in 

 cooperative field tests is reported. Leguminous seeds are being distributed for 

 the production of gi'een manure crops. The most desirable crops for this pur- 

 pose are san hemp and the Bengal bean. Reports of the committees on cultiva- 

 tion, fertilization, and irrigation on irrigated plantations and on cultivation and 

 fertilization on unirri gated plantations are given, together with a discussion 

 thereof. 



Breeding' sugar cane {.Jour. Heredity, 7 {1916), No. 9, p. 405). — This is a 

 brief note on sugar cane breeding in Porto Rico. Hand pollination has been 

 found almost impossible, due to the smallness of the flower, the height at 

 which the inflorescence is produced, and its brittletiess. Wind pollination has 

 been accomplished by planting a pollen-sterile variety on the leeward side of a 

 pollen-fertile variety. 



Studes in Indian sugar canes. — II, Sugar cane seedlings, including some 

 correlations between morphological characters and sucrose in the juice, 

 C. A. Barber {Mem. Dept. Agr. India, Bot. Ser., 8 {1916), No. 3, pp. 103-199, pis. 

 32, figs. 2). — This gives a detailed account of studies of sugar-cane seedlings. 



In an effort to increase sugar production in India, sugar-cane seedlings have 

 been propagated at Coiuibatore in Madras, where the cane flowers profusely. 

 The seedlings obtained are enumerated and described by periods, representing 

 the periods of seed production. Variations in nine morphological characters, 

 viz, vigor and size, general habit of growth, erectness of young shoots, tillering, 

 leaf types, width of leaf, color of leaf, color of cane, and thickness of cane, and 

 in the sucrose percentage in the juice are discussed in detail. A number of cor- 

 relations between the morphological characters of the seedlings and the richness 

 of their juice have also been studied. These correlations are as follows: Leaf 

 width and sucrose, length of leaf and sucrose, leaf nodule and sucrose, thickness 

 of cane and sucrose, length of cane and sucrose, cane module and sucrase, leaf 

 width and thickness of cane, leaf width and total weight of .seedling, leaf width 

 and tillering, and color of cane and sucrose. 



Production of sugar in the United States and foreign counti'ies, P. Ei-liott 

 {U. S. Dept. Agr. Bui. 413 {1917), pp. 7(?).— Statistics are given for the United 

 States and 37 other countries on the production of cane and beet sugar for the 

 period from September 1, 1903, when the Brussels Convention went into effect, 



