136 GENETICS [BoT. Absts., Vol. VII, 



bivoltin, the latter hatching at once. Females of the fourth and fifth pair produced uni- 

 voltins only. All bivoltin moths of 1918 produced yellow eggs which hatched in the spring 

 of 1919. — Thus while in the typical univoltin race only one kind of egg exists, in the acci- 

 dental bivoltins there are two kinds, summer eggs and winter eggs, the latter hibernating. — 

 Accidental bivoltins, therefore, do not transmit wholly and immediately to all their descend- 

 ants the aptitude to produce alternatingly summer and winter eggs, but to a certain num- 

 ber only. J'he new character appearing in bivoltins is not, therefore, represented by a 

 mutation in the de Vriesian sense. — Isabel McCracken. 



907. Lehmann, Ernst. Neuere Oenotherenarbeiten. (Sammelreferat II). [New work 

 with Oenothera. (Composite review).] Zeitschr. Bot. 12:61-85. U fig- 1920.— Paper is 

 second of a series of composite reviews of the latest Oenothera literature, the first having 

 appeared in 1917 (loc. cit., 10:517), and presents in an extended discussion amplified by 

 original diagrams the work of Atkinson, Bartlett, Davis, Kranichfeld, Lotsy, Renner, 

 and DE Vries (1915-1920) in so far as the investigations of these authors throw new light 

 upon the two chief questions:— (1) Is Oe. Lamarckiana a hybrid or a pure species? (2) How 

 do mutations appear and thus build up new species in the genus Oenothera? — The following 

 classification of recent investigations is also included: (1) de Vries, evidence obtained from 

 crossing, (a) The establishment of the hypothesis of heterogamy; (b) Twin hybrids. (2) 

 Honing, anatomical evidence upon the hybrid nature of Oe. Lamarckiana. (3) Heribert- 

 NiLSSON, the red-nerve factor and the impossibility of its existence in a homozygous con- 

 dition. (4) Bartlett, mass-mutation in Oe pratincola. (5) Renner, sterile seed and selec- 

 tive pollen-tube growth. (6) Lutz. Gates, Stomps et al., chromosome counts in gigas and 

 lata forms. — Paul A. Warren. 



908. Linhart, G. a. A new and simplified method for the statistical interpretation of 

 biometrical data. Univ. California Publ. Agric. Sci. 4: 159-181. 12 fig. 1920.— Graphic 

 method of fitting Gaussian and Galton-McAlister frequency curves. Use of latter urged 

 when deviations are large in comparison with mean. — Raymond Pearl. 



909. LiPPiNCOTT, Wm. a. Improving mongrel farm flocks through selected standard- 

 bred cockerels. Kansas Agric. Sta. Bull. 223. 48 p., 30 fig. Jan., 1920.— Four pens, ten 

 each, of mongrel females were mated respectively with a standard-bred White Orpington 

 male, a standard-bred Barred Plymouth Rock male, a standard-bred South Carolina White 

 Leghorn male, and an unselected mongrel male. Standard-bred males in most cases had 

 high-laying pedigree. In second year, offspring from these matings were again bred in same 

 numbers to other males of same varieties. This was repeated with second generation. 

 Decided improvement in laying qualities was obtained through the Plymouth Rock and 

 White Leghorn males. Through the mongrel males nearly as good results were obtained. 

 The White Orpington males produced no improvement. Latter is explained through lack of 

 pedigree in standard-bred males. In all cases fair uniformity in type and color was obtained 

 by the third generation through the standard-bred males. Laying records are given for 

 those offspring only that were selected for mating. — H. G. May. 



910. Little, C. C. Note on the occurrence of a probable sex-linked lethal factor in mam- 

 mals. Amer. Nat. 54:457-460. Sept.-Oct., 1920.— The sex ratio of a highly inbred strain 

 of Japanese waltzing mice, all descendants of one pair of individuals, was 53.2 ± 5.7, while 

 that for inbred non-waltzing mice was 103.1 ± 2.8, a difference in the ratios of 7.9 times the 

 probable error. Further expected results were obtained in the number of males resulting 

 from reciprocal crosses of waltzing by non-waltzing stock. Data obtained from back-crosses 

 of the lethal-carrying females on Fi's of normal by waltzing and the litter size of a pure strain 

 of waltzing mice, were also in keeping with the assumed recessive sex-linked lethal. Pre- 

 liminary report. — Sarah VH. Jones. 



911. Little, C. C. Factors influencing the growth of a transplantable tumor in mice. 

 Jour. Exp. Zool. 31: 307-326. Oct. 5, 1920.— The tumor used in the experiments was found 

 as a spontaneous growth in a strain of Japanese waltzing mice by Tyz?er. It had been 



