Vererbung, Variation, Mutation. 77 



Die Autoren berichten ferner über die Wirkung intravenöser Injektion der 

 genannten Stoffe auf experimentell erzeugte Placentome, auf den Verlauf der 

 Wundlieilung bei weißen Mäusen und auf die Organe normaler Meerschweinchen. 



Weishaupt (Berlin). 



Hierzu: Nr. 166, 184, 194, 198, 266, 271. 



Yerer billig, Variation, Mutation. 



178) Davis, B. M., The behavior of hybrids between Oenothera biennis 

 and 0. grandiflora in the second and third generations. In: Amer. 

 Natural, Bd. 47, S. 449—476, 547—571, 17 Fig., 1913. 



The writer refers to his Fg cultures of 0. grandifloya X 0. biennis, and des- 

 cribes a few of the types they contain. His main interest is in producing a 

 plant agreeing with (). laniarckiana, in which he has not yet met with success. 

 Among the Fg offspring, dwarfs were obtained in one large family in the ratio 

 of about 1 dwarf to 10 talls, and an F3 family yielded about 1 dwarf in 16. 

 Davis has, however, neglected to ascertain whether the parents of his cross 

 were throwing dwarfs and in what proportion, though we may safely conclude 

 that one of them probably was doing so. 



In addition, Davis found several forras which are parallel to the de Vrie- 

 sian mutants, including (1) ellipüca, (2) a mutant which is probably triploid, 

 and (3j his fig. 14 which (though he does not recognize it) very probably repre- 

 sents a lata -like mutant having 15 chromosomes. The description of the mass 

 of the hybrids is too vague to be of service, and the nature of the "progressive 

 evolution" in flower-size and leaf-crinkling, of which the writer speaks, is 

 not clear. 



The presence or absence of red in the papillae on greeu portions of the 

 stem is believed to be an alternative character, though the ratios of the types 

 depart widely from the Mendelian ratio. 



In the discussion, the writer questions whether the results are in accord 

 with "a strict Mendelian conception of the stability of factors", and adopts the 

 reviewer's conception that the mutations of 0. lamarcMuna are due to "instability 

 of germinal Constitution'', resulting from crossing in the ancestry. 



Gates (London). 



179) Lacy, 3lary G., A discussion of the results obtained by crossing Zea 

 mais L. (Mais Djagoeng) ( — Reana luxurians Dut. — Teosinte) and J5mc/*- 

 laena mexicana Sclirad. In: Amer. Natural, ßd. 47, S. 511 — 512, 1913. 



Abstract of a paper by G. E. van der Stok in Teysmannia, Vol. 21, 1910. 



Gates (London). 



180) Whiting, P. W., Viability and coupling in Brosophila. In: Amer. 

 Natural, Bd. 47, S. 508—511, 1913. 



Five pairs of red-eyes flies {Brosophila^ and five pairs of white-eyed stock 

 from another source were on November 29, 1911 put together in a glass jar 

 to test their relative viability. If allowed to multiply indefinitely, the white being 

 recessive, the proportions expected would be 2 white males: 2 red males: 3 red 

 females: 1 white female, or disregarding sex, a proportion of 5 red to 3 white. 

 Actually the proportion of reds was much greater, — 14:1 on Feb. 12, 21.5 : 1 on 

 Mar. 13 and 22.7 : 1 on April 12*^. This is explained as due entirely to the 

 greater viability of the red-eyed flies. A few flies had eyes greatly reduced in 

 size, and one had spotted eyes. 



