1929] Navashin: Triploidy in Creyis 39") 



13. It is difficult to imagine how the resulting trisomic types can 

 play any role in species formation, although they represent first-class 

 material for genetic analysis, thanks to the clear morphological difiPer- 

 ences of the chromosomes. There is some probability, however, that 

 fragmentation of chromosomes may take part in the formation of 

 certain Crcpis species. 



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