(20) Neue Literatur. 



Molz, E., 1920. Versuche zur Ermittlung des Einflusses äußerer Faktoreri 

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Moore, C, R. , 1920. The production of artificial hermaphrodites in mam- 

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Morgan, T. H., 1919. The genetic and the operative evidence relating to 



secondary sexual characters. Publ. Carn. Inst. Washington. 108 S. 

 Morgfan, T. H., 1920. The genetic factor for hen-feathering in the Sebright 



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 Morgan, T. H., 1920. The effects of castration of hen-feathered Campines. 



Biol. Bull. 3». 

 Morgan, T. H., 1920. Variations in the secondary sexual characters of the 



fiddler crab. Am. Nat. 54. S. 220—246. 6 Textf. 

 Morgan, T. H., 1920. Whitman's work on the evolution of the group of 



Pigeons. Science, N. S. 51. S. 73—80. 



Müller, H. J., 1920. Further changes iu the white eye series of Drosophila 

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Newman, H. H., 1921. On the occurence of paired madreporic pores and 

 pore canals in the advanced bipennaria larvae of Asterina (Pasiria) 

 miniatai together with a discussion of the significance of similar 

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Northrop, J. H., 1920. Concerniog the hereditary adaptation of organisms 

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Onslow, H., 1920. Inheritance of Wing colour in Lepidoptera. IV. Melanism 



in Boarmia abietaria. Journ. of Genetics. 10. S. 135 — 140. 1 Taf. 

 Orton, T. H., 1921. Sex-change in the native oyster. Nature. 107. S. 580. 



Pap, E., 1921. Über Vererbung von Farbe und Zeichnung bei dem Kaninchen. 

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Payne, F., 1920. Selection for high and low bristle number in the mutant 

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Pearson, R.. 1920. The fundamental problem of practical statistics. Bio- 



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 Petersen, H., 1920. Bildung einer überzähligen Linse bei Rana temporaria. 



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Pezard, A., 1921. Numerical law of regression of certain secondary sex 

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Ptizenmayer, E. W., 1920. Bastardierungen von Cavicorniern inTranskaukasien. 

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Philiptsclienko, J., 1916. Variabilite et heredite du crane chez les mammi- 

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Philiptsclienko, J., 1916. Les especes biologiques du Chermes et leur diffe- 

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