No. 557] INHERITANCE OF MAMM2E IN SWINE 



263 



lar type is of interest, although 

 The rank is as follows : 



Between 5th and 6th 16.09 



Between 6th and 7th 4.023 



Between 2d and 3d 3.25 



Between 4th and 5th 2.7 



Between 1st and 2d 2.2 



Between 3d and 4th 1.23 



Once more, if we discard the results between 5th and 

 6th, and 6th and 7th, because of small numbers, we find 

 the high per cent, of variability at the second pair. 



The point of appearance of the suppressed nipple vari- 

 ation was plotted in the same way and the following order 

 of appearance was found: 



6th pair 6.9 



2d pair 6.3 



5th pair 1.3 



4th pair U 



3d pair 0.5 



Inguinal pair 0.2 



1st pair 0.0 



Again the second pair is shown as the chief seat of 

 variation. It may be well to mention that while there 

 was a possibility of 1,138 mammae appearing in the 1st, 

 2d, 3d, 4th, and inguinal pairs, only 704 mammae could 

 have appeared in the 5th pair and 174 mammae in the 

 sixth, because of the small numbers of animals having 

 over ten and twelve mammae, respectively. 



