1918] FIELD CROPS. 237 



progeny showed 57.4 per cent fertility with normal isolation and 14.8 per cent 

 with' glass-tnbe isohition. Four races have been observed which can be ex- 

 pected to show as high fertility. Normal fertility with Petkuser rye from cross- 

 pollination, according to Ulrich (E. S. R., 14, p. 75G), is SO per cent. 



Plants were also found which showed a high fertility percentage but some- 

 what lower (10 to 20 per cent) than that for the races noted above. These 

 strains, however, have been observed through only two generations and consist 

 of a small number of Individuals. The author suggests that such plants be 

 designated as " half-fertile " to distinguish them from those of higher fertility. 



Individual plants setting from 10 to 20 per cent of seed have been observed 

 to produce only self-sterile progeny. They are to be considered, therefore, as 

 partly fertile modifications, or as extreme plus-variants of ordinary self-steril- 

 ity. Only through inheritance studies, therefore, is the genotypic nature of 

 partly fertile plants to be determined. Modifications which show such high 

 percentages of fertility as that of the high-fertility races have not been observed. 



The fertility percentage of high-fertility races did not appear to be depressed 

 by i.solation, although a marked retrogression in the quality and vitality of the 

 seetl and in the vitality of the progeny was observed. The plants remained 

 rather vigorous after the second isolation but after the third were almost 

 dwarfed. Whether strains of high self-fertility could be maintained for agri- 

 cultural purposes is still regarded as questionable. These races have the ad- 

 vantage of being practically independent of meteorological conditions, but in 

 every case observed the inferior quality of gi'ain occasioned by isolation has 

 been permanently established in the cross-pollinated progeny so that any ad- 

 vantage is apparently accompanied by this serious disadvantage. The author 

 concedes, however, that differences between those races, in respect to this char- 

 acter, may be encountered, and that through hybridization the vitality of the 

 race might be established without losing the advantages of self-fertility. The 

 progeny of such a hybrid must be constantly self-fertile, since it arises from 

 races having the same recessive character. 



The author notes the progress of experiments planned for further study of 

 the inheritance of sterility in an effort lO determine whether this character 

 lies solely in the ovule or is also expressetl in the pollen grain. 



Grain soi^hum seed, E. B. Babcock {California, Sta. Circ. Ill {1911), pp. 8, 

 flgf!. 6). — This is a popular discussion of the principles and methods of seed 

 selection for the improvement of grain sorghums, together with simple direc- 

 tions for field selection and for testing individual plant selections. 



The purification of soy bean varieties, D. F. Jones and H. K. Hayes {Con- 

 necticut State Sta. Rpt. 1916, pt. 5, pp. 348-353). — Variations in plant habit 

 and in flower and pod color observed in a variety of soy beans grown at the 

 station in 1913 led to individual plant selections within the variety during 

 1914. Differences in height, number of pods, color and shape of seed, yield, 

 time of flowering, color of flowers, and habit of growth were noted for 23 

 selections. Similar observations of selected plants within a strain grown as 

 Ito San indicated that the variety was quite pure. 



It is concluded that " these results simply show that a mixed variety of soy 

 beans can be purified and made uniform by selecting individual plants and 

 increasing their progeny." 



Harvesting' soy-bean seed, W. J. Mobse {U. 8. Dept. Agr., Farmers' Bui. 886 

 {1911), pp. 8, figs. 1). — Directions are given for harvesting, curing and handling, 

 thrashing, and storing soy beans when grown for seed. 



The sugar beet in Algeria, Vermeil {Bui. Agr. Alg6rie, Tunisie, Maroc, 22 

 {1916), No. 2-6, pp. 29-34)- — A- general discussion of sugar beet production in 

 Algeria, together with tabulated data comparing six varieties. 

 44073°— 18 4 



