38 GENETICS [BoT. Absts., Vol. IX, 



239 Key, Wilhelmine E. Heredity and social fitness; a study of differential mating in 



a Pennsylvania family. Carnegie Inst. Washington Publ. 29G. 102 p., 2 folded diagrams. 

 1920.— Object of the investigation was twofold: "First, to determine the mode of evolution of 

 the various lines of a great network with reference to traits which have direct bearing on social 

 efficiency; second, to study the variation in the grade of these traits and the relation of this 

 variation to the types of mating." The study is based on 1,822 individuals constituting 

 2 family networks of western Pennsylvania chiefly descended from 2 pairs of German immi- 

 grants of more than a centur}' ago. There is given about 70 pages of detailed family history 

 with characterizations of individuals and accompanied by 2 complete pedigree charts. Seven 

 lines of descent or strains are made out which show diverse types of evolution, some to in- 

 creased social efficiency and others to differing forms of degeneracy but each related to the 

 type of marriage selection involved.- — An attempt is made to express the distribution of 

 certain traits in terms of Mendelian inheritance. Calculating ability is shown to behave as 

 the expression of Mendelian dominance. "The assumption of a unit-character of varying 

 potency, or better, of a number of determiners which behave in unit-like fashion, would appear 

 to explain the phenomenon of inheritance for calculating ability as observed in these net- 

 works " Aggressiveness and perseverance are less satisfactorily shown to segregate in ac- 

 cordance with Mendel's law for presence or absence of determiners in the germ-plasm — : 

 The several lines are compared statistically with reference to: (1) Social efficiency, showing; 

 striking divergence; (2) fecundity, v/hich shows a noticeable drop in later generations of all 

 lines, but no more striking in the socially efficient lines than in the degenerate lines; (3) sur- 

 vival increases relatively in the socially efficient lines and decreases in the degenerate lines; 

 (4) differential migration, the more efficient migrating. Comparison of environmental op- 

 portunities with inherent tendencies seems to indicate the greater potency of the latter. 

 [See also Bot. Absts. 9, Entry 216.] — Howard J. Banker. 



2-40. Kniep, H. [German rev. of: Hertwig, Oscar. Allgemeine Biologic. (General 

 biology.) 5th improved and enlarged ed., 8 vo, xvi -f- 800 p. Gustav Fischer: Jena, 1920.] 

 Zeitschr. Bot. 13: 173-174. 1921. 



241. KoTTTJR, G. L. Cross-fertilization and sterility in cotton. Agric. Jour. India 16: 

 52-59. 1921. — Adaptations of cotton flower to both self- and cross-pollination are described 

 and predominance of self-fertilization noted. Vicinism amounting to 6 per cent was observed 

 when 2 easily distinguishable strains were grown side by side at Dharwar, India. Occurrence 

 of several manifestations of sterility, notably empty anthers and abortive ovules, was observed 

 in naturally pollinated stocks of Indian cottons; controlled self-fertilization during 6 genera- 

 tions did not increase these nor the rate of boll-shedding .^ — T. H. Kearney. 



242. Kristofferson, Karl B. Undersbkning av Fi och F2 generationerna av en spon- 

 tan bastard mellan vitkal och gronkal (mit deutschen Resume). [Investigation of Fi and Fj 

 generations of a spontaneous hybrid between white cabbage and green cabbage (with a sum- 

 mary in German).] Sveriges Utsadesf. Tidskr. 1921: 31-52. 8/?^. 1921.— The hybrid vi-as very 

 intermediate. The leaves of the parent plants had a green midrib, which, however, in white 

 cabbage became light red in the autumn. Fi has a dark red violet color. In Fa a segre- 

 gation into dark red violet, light red violet, and green nerves takes place according to the 

 ratio 9:3:4. Many characters show a continuous segregation in F2 with the qualities of the 

 parents as extremes. As to other characters the segregation was transgressive. Chloro- 

 phyll varieties were observed. In spite of the fact that Fo included nearly 14000 individ- 

 uals no plants similar to the grandparents were obtained. Some Fo plants resembled old 

 seedsmen's varieties of cabbage. — K. V. Ossian Dahlgren. 



243. L6cAiLLON, A. Sur les changements qu'on observe dans la reproduction et le d6vel- 

 oppement des Bombyx pol3rvoltins de Chine lors-qu'ils sont transportes et eleves en France. 

 [On the changes observed in the reproduction and development of poljrvoltine Bombyx of China 

 when they are raised in France.] Compt. Pond. Acad. Sci. Paris 168: 529-531. Mar., 1919.— 

 The author observes that under the climatic conditions of France, Chinese polyvoltin silk- 



