C52 
HEG65 SMITHSONIAN CONTRIBUTIONS TO KNOWLEDGE. 
Vert. Fat. <n 
192 
PReraACkhOUs REPTILES 
UNITED STATES. 
e 
BY 
JOSEPH LEIDY, M.D., 
PROFESSOR OF ANATOMY IN THE UNIVERSITY OF PENNSYLVANIA, CURATOR OF THE AC 
[ ACCEPTED FOR PUBLICATION DRCEMBER, 1864.] 
21\GS2L0, 4 
