INTRODUCTION. 



The chief object in preparing the present Catalogue has been to give a complete account 

 of all the species of Emydosaurians, Rhynchocephalia, and Amphisbsenians now in the British 

 Museum, and of those species which are known to exist in other Cabinets, but which arc 

 at present desiderata in the Museum, to enable travellers, collectors, and others to assist in 

 completing the National Collection. 



The woodcuts are those which were prepared to illustrate the series of papers on the 

 arrangement and determination of the species of these animals first published in the ' Pro- 

 ceedings of the Zoological Society,' and have been kindly lent by the Council of the Societ) 

 for the purpose. 



JOHN EDWARD GRAY 



British. Museum, September 7th, 1^72. 



