% 



1858 



UNITED STATES 



EXPLORING EXPEDITION. 



DURING THE YEARS 



1838, 1839, 1840, 1841, 1842. 



UNDER THE COMMAND OF 



CHARLES WILKES, U.S.N. 

 YOL XX. 



HERPETOLOGY. 



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, V7X-<Sa- 



A 



PREPARED UNDER THE SUPERINTENDENCE OF 



S; F. BAIRD. 



WITH A FOLIO ATLAS. 



PHILADELPHIA: 

 FEINTED BY C. SHEEMAN & SON. 



1858. 



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