Proceedings of the American Academy of Arts and Sciences, 



Vol. XLIX. No. 7. —September, 1913. 



CONTRIBUTIONS FROM THE ZOOLOGICAL LABORATORY 

 OF THE MUSEUM OF COMPARATIVE ZOOLOGY 

 AT HARVARD COLLEGE. — No. 239. 



ON THE SIZE OF LITTERS AND THE NUMBER 

 OF NIPPLES IN SWINE. 



By G. H. Parker and C. Bullard. 



