PROCEEDINGS 



OF THE 



ACADEMY OF NATURAL SCIENCES 



OF 



PHILADELPHIA 



1 8 8 O. 



I'UBLicATioN committee- 

 Joseph Leidy, M.D., Geo. H, Horn, M.D., 

 William S. Vaux, Thomas Meehan, 

 John H. Redfield. 



Editor: EDWARD J. NOLAN, M.D. 



PHILADELPHIA: 



ACADEMY OF NATURAL SCIENCES, 

 S.W. Corner Nineteenth and Race Streets. 



1881. 



