The American Naturalist 



A Monthly Journal, e.tabluhed in 1867. Devoted to the Advancement of the Biological Science. 





11. Rejtections^njhe o«o°G? my r 0f Biologicftl ^ 

 V. Note, and ^Literature^: Notes on Ichthyology. 



L Factors and Unit Charactera In Mendelian 



Heredity. Professor T. H. Morgan 

 II. V ^ c ^ ftn D ^^^ ti |? n °? ** e j Cbseto«Mith» of 





HL Simplification of Mendelian Formula. Profes- 

 l! M ert ^ bmte Paleontolc «y- Professor Roy 



CONTENT8 OF THE APRIL NUMBER 



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