No. 1, July, 1920] GENETICS ]Q7 



lowing arguments: (1) The plasma may increase, though only dead material is given to it as 

 nurture, while pangens are supposed to be "living" things. -(2) If this i not yet the then 



the organism analyses all food material into simple groups of molecule and abolishes all 1 races 

 of organised structure. < >n these grounds the wrriter denies the existence of living "genes," 

 "pangenes," <>r how these living particles may be called and accepts only molecules as I mill- 

 ing stones for the organism. To go more into details in t hese <|ii< f ions, t he author thinks it 

 thoroughly useless, because of our ignorance about the Bimplesl proce e of formbuilding in 

 living material. For instance the problem of the real nature of the zygote in animals. This 

 zygote is generally accepted to be a double-Cell, resull ing from equivalent pari -, one from t he 

 father, one from the mother. Hut these parts are really not equivalent. First, the zygotic 

 plasm is only supplied by the mot her; t he zygote 1 hereforc is not a double-eel 1, but a simple cell 



with a double-nucleus. According to the conceptions of Schaxel, the zygotes have only one 

 kind of plasma and two kinds of nuclei; along these lines the difference of reciprocal crosses 

 as observed in some cases, may perhaps be explained. — Even if by experimental researches 

 the alternative "mutation or crossing, cause of evolution" were decided in one or the other 

 direction, then our explanation of the evolutionary process would only have begun. The 

 significance of nucleus and plasm and their interrelation will remain a further problem to 

 be solved. Perhaps the study of Oenotheras (nucleus-chimaeras as the author calls them) 

 will bring us still many new facts in this direction. — M. J. Sirks. 



653. Lotsy, J. P. [Dutch rev. of: Anonymous. Wanted, photographs of twins. Jour. 

 Heredity 9: 262. Oct., 1918. (See Bot. Absts. 2, Entry 232.)] Genetica 2 : 89-90. Dec, 1920. 



654. Lotsy, J. P. [Dutch rev. of: DeVries, Hugo. Twin hybrids of Oenothera Hookeri 

 T. and G. Genetics 3: 397-421. Sept., 191S. (See Bot. Absts. 3, Entry 2111.)] Genetica 

 2:88-89. Jan., 1920. 



655. Lotsy, J. P. [Dutch rev. of: Duerden, J. E. Absence of xenia in ostrich eggs. 

 Jour. Heredity 9:243-245. Oct., 1918. (See Bot. Absts. 1, Entry 1479.)] Genetica 2: 54. 

 Jan., 1920. 



656. Lotsy, J. P. [Dutch rev. of: Embody, G. C. Artificial hybrids between pike and 

 pickerel. Jour. Heredity 9: 253-256. Fig. 4-5. Oct., 1918. (See Bot. Absts. 2, Entry 25.)] 

 Genetica 2 : 59-60. Jan. , 1920. 



657. Lotsy, J. P. [Dutch rev. of: Ness, H. Hybrids of the live oak. Jour. Heredity 9: 

 263-268. Fig. 6-8. Oct., 1918.] Genetica 2: 77-78. Jan., 1920.— See Bot. Absts. 1, Entry 

 1275. 



658. Lotsy, J. P. [Dutch rev. of: Pearl, Raymond. Some commonly neglected factors 

 underlying the stock breeding industry. Ann. Rept. Maine Agric. Exp. Sta. 1917: 1-2S. 1917.] 

 Genetica 2 : 79. Jan., 1920. 



659. Lotsy, J. P. [Dutch rev. of: Pearl, Raymond. The experimental modification of 

 germ cells. I. General plan of experiments with ethyl alcohol and certain related substances. 

 Jour. Exp. Zool. 22:127-164. Jan., 1917. — Ibid. II. The effect upon the domestic fowl of 

 the daily inhalation of ethyl alcohol and certain related substances. Ibid. 165-1S6. Jan., 

 1917. — Ibid. III. The effect of parental alcoholism, and certain other drug intoxications upon 

 the progeny. Ibid. 241-310. Feb., 1917.] Genetica 2 : 79-80. Jan., 1920. 



660. Lotsy, J. P. [Dutch rev. of Pearl, Raymond. On the differential effect of certain 

 calcium salts upon the rates of growth of the two sexes of the domestic fowl. Science 44: 6S7- 

 6S8. No. 10, 1916.] Genetica 2 : 78. Jan., 1920. 



661. Lotsy, J. P. [Dutch rev. of: Popenoe, P. Will morality disappear? Jour. Heredity 

 9: 269-270. Oct., 1918. (See Bot. Absts. 2, Entry 259.)] Genetica 2: SI. Jan., 1920. 



