PROCEEDINGS 



OF THE 



ACADEMY OF NATURAL SCIENCES 



or ^- ^e>- 



O 



PHILADELPHIA. 



1871. 



PUBLICATION COMMITTEE. 



Joseph Leidy, M.D.^ Wm. S. Vaux, 



KoTJEiiT Bkidoes, jVI.I)., Geo. W. Tryon, Jr.., 



Edw. J. Nolan, M.D. 



PHILADELPHIA: 



ACADEMY OF NATURAL SCIENCES, 



Corner of Broad and Sansom Streets. 



1871. 



