90 GENETICS IBot. Absts., Vol. VI, 



643. Woolsey, Theodore S., Jr. Prevention of forest devastation. Jour. Forestry 18: 

 326-328. 1920. 



644. Woolsey, Theodore S., Jr. [Rev. of: Goblet d'Alviella, Felix. Elements de 

 sylviculture. Vol. 1, 383 p.; Vol. 2, 269 p. Marcel Reviere: Paris, 1919.] Jour. Forestry 18: 

 296-297. 1920. 



GENETICS 



G. H. Shull, Editor 

 J. P. Kelly, Assistant Editor 



645. Akerman, A. Speltlike bud-sports in common wheat. Hereditas 1: 116-127 6 fig, 

 1920. 



646. Akerman, A., Hj. Johansson, and B. Platon. Fortsatta undersokerningar rorande 

 suckerhalt och torrsubstanshalt hos nagra hostvetesorter. [Continued examinations on the 

 percentage of sugar and dry-substance in some varieties of winter wheat.] Sveriges Utsadesf. 

 Tidskr. 28: 216-224. 1918.— Continuation of senior author's work on winter killing and frost 

 resistance. [See Bot. Absts. 5, Entry 254.] — K. V. Ossian Dahlgren. 



647. Altenburg, Edgar, and Hermann J. Muller. The genetic basis of truncate wing, 

 — an inconstant and modifiable character in Drosophila. Genetics 5: 1-59. 1 fig. Jan., 1920. 

 — Truncate wing is an inconstant character varying from short truncate to normal. It is 

 still modifiable after 100 generations of selection, and even the best truncate lines threw 10 

 per cent of normals. The variation is both somatic and genetic, and there is a close resem- 

 blance to the cases quoted in favor of factorial inconstancy. Yet a detailed analysis shows 

 that the genetic variation is due to sorting out of factors, not to fluctuation of individual genes; 

 since when the genetic constitution was maintained constant in a new type of "pure line" 

 experiment carried out by means of "identifying factors," selection was without effect. — 

 The truncate character is due to several factors, at least one in every chromosome except the 

 fourth. The main factor, without which the character rarely appears, is in the second chromo- 

 some. This factor is lethal when homozygous, hence the impossibility of obtaining a pure 

 stock. The low number of normals thrown in selected stocks is due to a "balancing" lethal 

 in the opposite chromosome, which kills off the normals (except those that escape by crossing 

 over). The truncate factor in the third chromosome reduces the fertility of females homo- 

 zygous for it, thus also preventing the obtaining of pure stock. The first chromosome factor 

 is not lethal and does not reduce the fertility.— The authors point out the applicability of the 

 method of "identifying factors" to other complex genetic cases, as in human heredity. — 

 Alexander Weinstein. 



648. Anderson, W. S. Bloodlines of genetic value. Science 52: 41. July 9, 1920.— 

 Author's abstract of paper read before seventh annual meeting of the Kentucky Academy of 

 Science, Lexington, May 8, 1920:— In the domestic breeds of live stock great sires seldom pro- 

 duce more than one or two sons that are greater progenitors than themselves. This means, in 

 blooded stock, that the greatness of any given blood line is handed on by one or two in any 

 one generation, the others of the generation merely add members. In support of the state- 

 ment, the great sires of nine breeds of domestic animals were cited and the few sons of each 

 were named who have been instrumental in handing on the breeds. — W. S. Anderson. 



649. Anonymous. Death of W. Schallmayer. Jour. Heredity 11: 155. April, 1920. 



650. Anonymous. Moral qualities and eugenics. Jour. Heredity 11: 189. April, 1920. 



651. Anonymous. Were the black-and-white Holsteins originally red-and-white? Jour. 

 Heredity 11: 155. April, 1920. 



