Proceedings of the American Academy of Arts and Sciences. 

 Vol. XXXVIII. No. 18. — January, 1903. 



CONTRIBUTIONS FROM THE ZOOLOGICAL LABORATORY OF THE 

 MUSEUM OF COMPARATIVE ZOOLOGY AT HARVARD COLLEGE. 

 E. L. MARK, DIRECTOR. — No. 13G. 



MENDEL S LAW OF HEREDITY. 



By W. E. Castlk. 



