598 



Journal of Agricultural Research 



Vol. XX, No. 8 



Table II. — Original data on the F 2 , F 3 , and F i offspring from a cross of a mule-foot 

 boar on Duroc- Jersey sows — Continued. 



Syndactylism has been recognized as an inherited character in man 

 by Lewis and Embleton (6), 1 Lewis (5), and Pearson (7) ; in poultry by 

 Davenport (3); and in swine by Spillman (9). In man there is prob- 

 ably one main dominant factor allelomorphic to normal; and the case 

 shows simple Mendelism as we now understand it, although both Lewis 

 and Embleton and Pearson were not inclined to such a view. In poultry, 

 Davenport concluded that syndactylism was very imperfectly domi- 

 nant to its allelomorph, normal toes. Syndactylism versus cloven- 

 foot in swine has been cited as an illustration of monohybridism in a 

 number of textbooks, but no published data are available. Spillman 

 states : 



It is interesting to note that in crosses between mule-foot hogs and ordinary breeds 

 the mule-foot character seems to be dominant. 



1 Reference is made by number (italic) to " Literature cited," p. 604. 



