No. 2, March, 1921] GENETICS 131 



881. East, E. M. Population. Scientific Monthly 1920: 603-604. June, 1920.— The 

 author discusses the question of population increase in relation to increase of food. He 

 shows that present figures as to the world's population and food and their rates of increase 

 are entirely in accord with the conclusion of Malthus. Discussing the increase by races, he 

 concludes that the white race is increasing much more rapidly than either the yellow or 

 black race. China is practically stationary as to population, India and the South Seas have 

 a slow increase, and Japan has a high rate. The blacks are increasing only in this country, 

 the number of negroes in Africa remaining practically stationary. On the other hand, all 

 the white races except in France are increasing at fairly high rates. Wars, even one as great 

 as the last, seem to have no appreciable effect on the upward march of population. — Turning 

 to the United States, he shows that the law of diminishing returns has begun to apply to 

 agriculture and he calls attention to the fact that future increase in agricultural production 

 is definitely limited. To prevent the population of this country from crowding too closely 

 on the means of subsistence he offers the following remedies : First, a restriction of immigra- 

 tion; second, education; third, equitable readjustment in many of our economic customs; 

 and, last, natural marriage selection — a somewhat increased birth rate in families of high 

 civic value, and among the rank and file a restriction of birth commensurate with family 

 resources. — Lowell J. Reed. 



882. Engledow, F. L. Inheritance in barley. I. The lateral florets and the rachilla. 

 Jour. Genetics 10: 93-108. 3 fig. Aug., 1920.— Data are offered showing Mendelian segrega- 

 tion in F2 generations of crosses between smooth and bristly rachillae. A one-factor difference 

 is found. The problem of the inheritance of lateral florets is discussed and data bearing on its 

 solution presented. Several forms of lateral floret differing either in fertility or shape and 

 size of glume afford to this author instances of multiple allelomorphism. Histological study 

 of the developing lateral florets at different stages is needed to correlate Mendelian char- 

 acters with histological structures. — F. P. Bussell. 



883. Faber, Harold. Foreword by Sir Robert Greig. Forage crops in Denmark. 

 ix + 100 p. Longmans, Green & Co. : London, 1920.— See Bot. Abstracts 7, Entry 22. 



884. Garber, R. J., and P. J. Olson. A study of the relation of some morphological char- 

 acters to lodging in cereals. Jour. Amer. Soc. Agron. 11: 173-186. 1 pi, 2 fig. May, 1919.— 

 Authors mention the perplexing problem of producing non-lodging small grains possessing 

 high yielding capacity. In 1916 a project was organized to determine whether some simple 

 morphological character is closely related to lodging or non-lodging. Extreme varieties for 

 lodging in wheat, oats and barley were selected and study made of correlation between lodg- 

 ing behavior and average size of culm, average size of vascular bundles, average area of 

 sclerenchyma, thickness of culm wall, length of lignified cells, and thickness of lignified cell 

 wall. None of these characters except thickness of cell wall seems closely related to lodging. 

 Lodging in cereals is dependent on so many factors of unequal value that no one factor seems 

 correlated closely enough with lodging to be of much value as selection index. In oats and 

 barley the average number of vascular bundles was found to be correlated with average diame- 

 ter of culm. — Geo. K. York. 



885. Gates, R. Ruggles. Heredity and eugenics. Eugenics Rev. 11: 193-201; 12: 1-13. 

 1920.— Summarizes with comments and some discussion recent research as bearing on human 

 heredity under the main subjects of physical characters, mental characters, the limits of 

 heredity and the eugenical, social and world aspects, with a bibliography of fifty numbers.— 

 H. J. Banker. 



886. Georgesoix, C. C. Summary of the work at the several stations. Rept. Alaska 

 Agric. Exp. Sta. 1917: 5-33. PI. 1-2. 1919.— The author describes some new varieties pro- 

 duced by crossing; and presents the results of variety and cultural tests of horticultural and 

 farm crops; and also briefly discusses the value of various ornamental crops for Alaskan 

 conditions. — H. K. Hayes. 



