1918] FIELD CROPS. 233 



still less iu .1 given season than the standard deviations, and there is no vei-y 

 general tendency for the coefficients of variability to maintain a definite order 

 of values. That is to say, the differences of coefficients of variability of the 

 four strains seem to be fairly well described, with certain exceptions noted in 

 the paper, as random fluctuations. 



" The upper ears have a significantly larger mean value in length, weight, and 

 circumference than have the lower ears on the same stalks. The means with 

 respect to weight, length, and circumference of single ears are in each case 

 larger than the corresponding means for the lower ears of the same plat. The 

 me uis with respect to weight and circumference are also in general larger than 

 these means for upper ears of the same plat. However, strange as it may 

 appear, the mean lengths of single ears are on the whole less than those of 

 upper ears. A striking fact in the comparison of the single ears with the upper 

 and lower ears is the greater standard deviation in the weight of single ears. 



" Taken as a whole, there are no significant differences in [erect- and declining- 

 ear] strains with respect to the characters considered. In view of the sug- 

 gestion that ears are declining because of their greater weight, it is a fact of 

 special interest that the- declining ears are not on the whole heavier than the 

 erect ears. 



"The ears of the low-ear strain are on the whole significantly larger in mean 

 length, circumference, and weight than those of the high-ear strain, but there 

 are a few exceptions. In each of the eight years considered the mean number 

 of rows of kernels on ears is larger for the low-ear strain than for the high- 

 ear strain. The standard deviation of number of rows of kernels in each year is 

 distinctly gi-eater for the low ears than for the high ears, and the standard 

 deviation of circumference of ears is in general larger for the low-ear strain 

 than for the high-ear strain." 



[Nitrate experiments on " Nili " maiz^] (Min. Agr. [Egypt's Circs. 22 

 (1912), pp. 4; 43 [1913], pp. J,; 48 [191^], pp. 7; 11 {1915), pp. 11; 81 (1916), 

 pp. 9). — Experiments in the fertilizing of " Nili " maize with sodium nitrate 

 and the so-called baladi and kufri manures are reported. These experiments 

 have been conducted since 1911 and now embrace 50 demonstration farms in the 

 three provinces of Gheezeh, Qaliubia, and Menoofeeyeh. The results obtained 

 in each province are tabulated, and the general conclusions are as follows: 



The use of nitrate of soda in maize cultivation apparently increased the yield 

 4.5 ardebs (25.2 bu.) after berseem and 3.5 ardebs after wheat above the yield 

 secured from the use of kufri or baladi manures. Acid phosphate had no im- 

 mediate effect on the crop. The use of 150 kg. of sodium nitrate per feddan 

 (315 lbs. per acre) is recommended for Gheezeh Province when applied in 

 two installments, one at the time of thinning and the second at the time of 

 hoeing. The best results were obtained when from 75 to 100 loads of baladi 

 manure was applied at the time of plowing and the nitrate added as indicated, 

 but if baladi manure is not available, from 150 to 200 kg. of sodium nitrate 

 are recommended. 



Cotton variety tests for boll-weevil and wilt conditions in Georgia, A. C. 

 Leavis and C. A. McLendon (Ga. Bd. Ent. Bui. 46 (1911), pp. .5-34, figs. 3).— 

 Extensive variety tests with long-staple upland cotton and Sea Island cotton at 

 numerous centers in Georgia are reported in an effort to ascertain the varieties 

 best suited for growing under boll-weevil and wilt conditions. For southern 

 Georgia, Lewis 63, Desoto, Oouncil-Toole, Dillon (for sandy soils), and Dix- 

 Afifi are deemed best, while Cleveland, Toole, and Cook proved well adapted 

 to most sections of northern Georgia. 



