No. 2, September, 1920] GENETICS 225 



ear type. — In breeding for early maturity aut hor recommends select bag early-maturing plants 

 in the field instead of the longer process of elimination of the late-maturing types in the 

 variety by gradual acclimatization. — In breeding for drought -resist ance 1 he greatest difficulty 

 to be overcome is the "blasting" effect of hot, dry winds on pollen viability, although in BOme 

 districts this is obviated by planting at the proper time. It is stated that while breeding 

 may produce a drought-resistant pollen it must be borne in mind that the limitation of mois- 

 ture in the soil is also a contributing factor in low yields. — J. H. Kcmpton. 



1695. White, Orland E. [Rev. of: East, Edward M., and Donald F. Jones. Inbreed- 

 ing and outbreeding. U x 21 cm., 285 p., 46 fig. J. B. Lippincott: Philadelphia, 1919.) 

 Torreya 20: 32-34. Mar.-Apr., 1920.^See also Bot. Absts. 4, Entry 571 ; 5, Entries 437, 1607. 



1696. Wiogans, C. C. Some factors favoring or opposing fruitfulness in apples. Missouri 

 Agric. Exp. Sta. Res. Bull. 32: 1-60. 6 fig. 1918. — Studied individual fruit spurs of six com- 

 mercial varieties of apples. Three varieties were known as annual bearers and these developed 

 fairly high percentage of blossoms each year while three were classed as alternate bearers. 

 Two of the annual bearers were able to develop blossoms in successive seasons on the same 

 spur in much greater proportion than other varieties observed. Bearing spurs ranged from 2 

 to 8 years in age, 3 to 6 or 7 years being most effective fruiting age. — Found slightly higher con- 

 centration of sap (freezing point method) in bearing than in non-bearing spurs and not-d 

 marked decrease in sap concentration in late June or early July. Sugar and starch were shown 

 by chemical methods to be present in slightly greater quantities in bearing than in non-bearing 

 spurs. Determined effect of girdling, fertilizers, cultural treatments, and etherization on 

 concentration of cell sap. — H. K. Hayes. 



1697. Wilder, Harris Hawthorne. Physical correspondence in two sets of duplicate 

 twins. Jour. Heredity 10: 410-420. Fig. 15-19. Dec, 1919. 



1698. Winters, A. Y. Eugenics, the war instinct and democracy. Jour. Heredity 10: 

 254-256. June, 1919. 



1699. Woods, Frederick Adams. Twins prove the importance of chromosomes. Jour. 

 Heredity 10: 423-425. Dec., 1919. 



1700. Woods, Frederick Adams. A definition of heredity— " Nature vs. nurture" not a 

 good expression. Jour. Heredity 10: 426-427. Dec, 1919. 



1701. Wriedt, Chr. The brindle colour in cattle in relation to red. Jour. Genetics 9: 83. 

 Dec, 1919. — Author concludes from records on Telemark breed in Norway that brindle is 

 dominant to red (and not a heterozygote between red and black as J. Carlson had concluded), 

 on the basis of the following: Brindle X brindle or brindle X red gives both brindle and red, 

 but red X red gives only red. Black is said to be very rare in this breed, the characteristic 

 colors being brindle and red. — J. A. Dctlefsen. 



1702. Zeleny, Charles. A change in the bar gene of Drosophila melanogaster involving 

 further decrease in facet number and increase in dominance. Jour. Exp. Zool. 30: 293-324. 

 9 fig. April 5, 1920. — Author, who has for some time been studying the effect of selection upon 

 the physical appearance and hereditary determiners ("bar gene") of the barred eye of Droso- 

 phila melanogaster, reports several mutants that have arisen in respect to this character. 

 Bar gene, which is sex-linked, is concerned with the production of an eye with a greatly re- 

 duced number of facets (an average of about seventy-five, instead of the usual eight hundred 

 of normal "full-eye" flies). The F t generation of bar by full-eye is nearly intermediate 

 between the parents. To avoid the effects of varying temperature, the flies of these data were 

 reared at uniform temperature. Though considerable variability occurs in facet number, 

 one male appeared, having only nineteen facets, a number markedly lower than the lowest 

 otherwise known for bar eye. This fly produced a race with average of twenty-two or twenty- 



