FIELD CP.OPS. 231 



growing several varieties of barley on clay and sandy soils. The yields ranged 

 from 811 to 2,150 lbs. of grain per morgen (1,285 to 3,410 lbs. per acre) ; 1,000 

 kernels weighed from 34.88 to 48.05 gm., and a hectoliter weighed from 63.9 to 

 69.65 kg. 



New directions in the work of the selection of maize, I. Rosen (Khoziaistvo, 

 1912, No. SI, pp. 1013-1020; ahs. in Internat. Imt. Agr. [72ome], Bui. Bur. Agr. 

 Intel, and Plant Diseases, S {1912), No. 10, pp. 2156-2159).— This article dis- 

 cusses a system of producing and using the first hybrid generation to secure 

 increased yields with maize, the objects of this system being to prevent self- 

 fertilization and to keep the 2 iTUrent strains pure. It is stated that the 2 

 strains may be kept pure by planting in alternate rows. The rows of 1 strain 

 are topped the same year and from these the hybrid seed is obtained, while the 

 plants of the other row supply the caj-yopses (for 2 years) required for the 

 preservation and propagation of that strain ; in the subsequent year the opposite 

 plan is followed. 



The following observations are noted : " The descendants of a self-fertilized 

 plant are always less developed and productive than the descendants of plants 

 naturally exposed in the fields to cross-fertilization ; this is true both of superior 

 individuals and individuals inferior in point of productivity to the average of 

 the type to which they belong. The greatest diminution in the growth and 

 yield in consequence of self-fertilization is found in the first generation, falling 

 off gradually in the subsequent generations down to a constant value. The pure 

 strains (or self -fertilized, coming from a single parent plant) are distinguished, 

 among themselves, by transmissible morphological characters. The retrogres- 

 sion of the fluctuating characters is observed with greater frequency in propor- 

 tion as we get farther away from the * mean morphological type ' characteristic 

 of a 'pure strain.' The crossing between 'brothers' and 'sisters' (between 

 male and female inflorescences, respectively, of 2 plants coming from a single 

 parent plant and belonging to the same generation) presents no advantage over 

 self-fertilization. Crossing between 2 self-fertilized strains of different types 

 yields a progeny which is not inferior in force of growth and productivity to 

 the plants never subjected to self-fertilization. 



" In crossing 2 self-fertilized strains the results from the reciprocal crosses 

 are identical. The seeds of Fi obtained by crossing pure strains according to a 

 determined scheme (combination) always exceed in yield the sowing material 

 produced by irregular pollination in the fields, from which the 2 strains them- 

 selves were derived. The productivity and morphological characteristics of the 

 hybrids of the first generation are therefore a function of that specified combi- 

 nation of pure strains, and are constantly repeated when the crossing is 

 renewed. In the first generation of hybrids (Fi) the degree of variability of 

 the individuals is not greater than that observed in the pure strains from which 

 such generation sprang. In the second generation of hybrids (F2) the degree 

 of variability is higher than in Fi. The productivity of F2 is lower than that 

 of Fi." 



Variety tests of imported maize, A. H. Rosenfeld (Rev. Indus, y Agr. 

 Tucumdn, 3 (1912), No. 2, pp. 51-58). — Results are given of tests conducted 

 with 16 varieties of maize. In general the yields were much better in 1912, 

 ranging from 387 to 3.535 kg. than in 1911, when they ranged from 234 to 2,675 

 kg. of grain per hectare. 



A new variety of maize, C. M. Conner (Philippine Agr. Rev. [English Ed.}, 

 6 (1913), No. 2, p. 96). — This new variety is a cross between the Mexican June 

 and a native white variety, and is named Moro. Preliminary tests have shown 

 it to yield better than the small native varieties and to make good meal and 



