The Behavior of the Chromosomes as 

 Studied through Linkage. 



By A. H. Sturtevant, 



Columbia University, New York City. 

 (Eingegangen am 15. März 1914.) 



A. Introduction p. 234 



Chromosome I: single crossing over . 



Double crossing over 



Triple crossing over 



Chromosome II: single crossing over . 



Double crossing over 



Chromosome III: variability uf linkage 

 Independence of the three chromosomes 



B. Chromosomes and Mendelism . . 

 Sex chromosomes and sex-linkage . . 



Special cases > 



Cytoplasmic inheritance 



"Reduplication": somatic segregation . 



Frequency of linkage 



The nature of Mendelian genes . . . 



C. Summary 



D. Bibliography 



E. Tables 



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A. Introduction. 



The idea that Mendelian genes which show linkage ("coupling" 

 and "repulsion", or "reduplication" of Bateson and his collaborators) are 

 located in the same or homologous chromosomes, and that the strength 

 of this linkage is dependent upon their nearness in the chromosomes, 

 was first proposed by Morgan ('lib, 'lie). The writer has attempted 

 (Sturtevant '13 a) to carry this idea further by showing that, when 

 several genes in a given pair of homologous chromosomes are studied. 



