4 AGRONOMY [BoT. Absts., Vol. IX, 



20. Cox, J. F. The Michigan plan for distributing improved crop varieties. Jour. Amer. 

 Soc. Agron. 13 : 82-84. 1921. — The plan includes varietal testing, plant breeding, corn improve- 

 ment, the provision of large increase fields, and the help of extension specialists and 

 county agents. A crop improvement association and a farm bureau seed department also 

 cooperate. — F. M. Schertz. 



21. Cross, W. E. The distance apart in which cane rows should be planted, Louisiana 

 Planter and Sugar Manufacturer 65: 233-235. / fig. 1920. — The 3-year results obtained in 

 Tucimaan with cane planted in rows 0.9-2.5 m. apart agree in general with those secured 

 at an earlier period in Louisiana, namely, the closer the rows, the greater the tonnage obtained 

 per acre of sugar cane and sugar. Cane should be planted in rows as close together as will 

 permit mechanical cultivation. — C. W. Edgerton. 



22. Dawe, M. T. Columbian Pita fibre.— Part II. Tropic Life 17: 2-4. 1921.— The 

 Pita fiber is of excellent quality and should sell readily for as much as henequen of Yucatan. 

 Certain manufacturers of fiber products have offered to take the entire output of the "pitales" 

 of Chiriguana for 3 years at the current market price of sisal. The chief drawback to the utili- 

 zation of Pita fiber is the lack of machinery for efficient extraction of the fiber. It is estimated 

 that 40 per cent of the fiber is lost by the present crude methods. A machine for extracting 

 the fiber is being constructed in New York according to plans developed by the author. It 

 is estimated an acre of land will support 5,000 Pita plants; each plant produces 30 leaves per 

 year in 2 cuttings. A conservative estimate places the yield of dry fiber under improved me- 

 chanical processes of extraction at 3,030 lbs. per acre. — H. N. Vinall. 



23. Downing, R. G. Thick or thin seeding for wheat. Agric. Gaz. New South Wales 

 32: 205. 1921. — Recommendations are made as to proper rate of seeding. — L. R. Waldron. 



24. Grimme, C. tjber einige Hiilsenfriichte aus der Levante und aus Kamerun. [Legu- 

 minous plants from the Levante and Kamerun.] Zeitschr. Untersuch. Nahrungs- u. Genuss- 

 mittel 40: 37^1. 1920. 



25. Guthrie, F. B. Analysis of Saltbush. Agric. Gaz. New South Wales 32: 207-210. 

 1921. — Ash analyses are given of Atriplex leptocarpxim {?), A, nummidaria, and Chenopodium 

 triangular e as possible sources of potash. In the 2 species of Atriplex 40 per cent of the pure 

 ash was composed of K2O. Notes are given on the value of saltbushes for fodder. Analysis 

 shows them to compare favorably with standard fodders. — L. R. Waldron. 



26. Guthrie, F. B., G. W. Norris, and J. G. Ward. The influence of atmospheric vari- 

 ations on the weight of bagged wheat. Agric. Gaz. New South Wales 32: 200-202. 1921. — A 

 bag of wheat was weighed daily for 2 years. Weight and absolute and relative humidity are 

 shown graphically. Variations in weight of wheat, of lesser intensity, were found to corre- 

 spond with variations in humidity. No coefficients are given and the data are not handled 

 statistically. — L. R. Waldron. 



27. IIarland, S. C. Manurial experiments with sea island cotton in St. Vincent in 1918-19, 

 with some notes on the control of certain diseases by spraying. West Indian Bull. 18: 20-33. 

 1920. — Author draws the following conclusions: (1) Cotton responds markedly to applications 

 of both artificial and organic manures after it has been grown on the same land for a number 

 of years; (2) the size of the crop, leaving pests and diseases out of account, is limited chiefly 

 by the supply of potash in the soil; (3) most cultivated lands of the colony show the rust dis- 

 ease, locally known by the name of "red leaf," which is the characteristic sign of potash 

 exhaustion; (4) phosphate is not to be recommended since the combination of this and potash 

 gave inferior yields to potash alone; (5) cotton-seed meal alone is not to be recommended. 

 The best practice would be to rotate sugar-cane with cotton, using cotton-seed meal and pen 

 manure for the former, and for the latter an artificial fertilizer containing potash; (6) maturity 

 is not affected by manurial treatment; (7) ratio of bolls to flowers is not affected by differ- 

 ences in manurial treatment; (8) in St. Vincent there is great uniformity in the time at which 



