April, 1920] GENETICS 147 



give very different results, even where both crosses could be made at all. — Previous treat- 

 ment of the sperm with mesothorium radiation or with methylene blue in two cases changed 

 the product of fertilization from the dysnothi to the pseudonothi. The author points out 

 that the result of a cross depends not merely on the harmony between the two nuclei but also 

 on the harmony between sperm nucleus and egg cytoplasm. The degree of relationship be- 

 tween species can not safely be determined by the results of hybridization. — Sewnll Wright. 



1006. Johnson, Roswell H. The determination of disputed parentage as a factor in 

 reducing*infant mortality. Jour. Heredity 10: 121-124. Mar., 1919. — The necessity of deter- 

 mining the parentage of a child under two years of age is pointed out, as it is below this age 

 that greatest mortality occurs due to lack of support and court decision does not admit of 

 physical resemblance because of immaturity. Methods which will lead to accurate results 

 would reduce the number of illegitimate children and lead to better care of the child and 

 hence reduce its mortality risk. Four such methods are discussed: (1) Alternative inherit- 

 ance of many abnormalities, (2) More uniform application of the alternative inheritance of 

 certain human traits, (3) Papillary ridges of the palm and sole, (4) Anthropometry. The 

 latter can always be applied and errors eliminated by correction factors. The method is 

 feasible and requires only a sufficient appropriation and an organization to carry on the 

 work. — M. J. Dorsey. 



1007. Kajanus, Birger. Ueber eine Kreuzung zwischen zwei Typen von Sommerweizen. 

 [On the crossing of two types of spring-wheat.] Bot. Notiser 1918:245-247. Nov., 1918. — 

 The varieties used were "Marzuolo americano" and what had been received from Svalof, 

 Sweden, under the name "Perl" spring-wheat. The crossing made was Perl 9 X Marzuolo cT. 

 The Perl is unawned and has pale leaf-auricles, the Marzuolo is awned and has strongly red 

 auricles. In the F 2 generation, the unawned condition of the Perl appeared to the awned 

 in the ratio of about 3: 1, and the strongly red color of the auricles of Marzuolo to the paler 

 color as 3: 1. In the F 3 generation all possible homozygous and heterozygous combinations of 

 the two characters appeared, the ratio in the segregating families remaining about the same. 

 — P. A. Rydberg. 



1008. Key, Wilhelmine E. Better American families. II. Jour. Heredity 10:80-83. Feb., 

 1919. — An analysis of the setting of a defective family in society, showing that only a few 

 individuals in a defective line of descent were able to respond to the customs and institu- 

 tions of their day, but that others, better endowed from the standpoint of inheritance, were 

 able through marriage into better stock and in some instances a change in the environment, 

 to rise above the level of the others in the social fabric. See next following Entry, 1009. — 

 M. J. Dorsey. 



1009. Key, Wilhelmine E. Better American families. III. Jour. Heredity 10: 107- 

 110. Mar., 1919. — Showing that such traits or trait complexes as ability to calculate, aggres- 

 siveness, and perseverance have certain heritable elements which behave in accord with the 

 principle of segregation. Percentages from data given support the following conclusions: 



(1) When both parents show low grade of ability, all the children are similarly of low grade, 



(2) When both parents show high grade, practically all the children are similarly endowed, 



(3) When one parent shows a low grade and the other a medium or high grade the increase in 

 the percentage of medium and high is proportionate to the grade of the abler parent. Two 

 instances from history are given in which an effective building up of trait combinations has 

 occurred and the possibility is pointed out of more accurate ratings in studies of constructive 

 eugenics through the tests of efficiency in the National Army. See next preceding Entry, 

 1008.— M. J. Dorsey. 



1010. Lankester, Sir Ray. The terminology of parthenogenesis. Quart. Jour. Microsc. 

 Sci. 63: 531-536. Apr., 1919. — "Parthenogenetic" applies only to virgin mother herself (not 

 to offspring), and is limited in cases of either (1) normal egg capable of sexual zygosis, or 

 (2) demonstrably a comparatively recent modification of such. These eggs, incorrectly 



