COMMISSION 



TO WHICH THIS PAPER HAS BEEN REFERPvED. 



Samuel Jackson, M. D., 

 Joseph Leidy, M. D., 

 Jeffries Wyman, M. D. 



Joseph Henry, 



Secretary S. I. 



o 



T. K. AND r. O. COLLINS, PRINTHES, 

 PII1LA11ELPIIIA. 



