Vlll INTRODUCTION. 



to me his observations on the reptiles of that state, as well as given me the use 

 of the dravrings done under his direction by Mr. Hill. 



With the colouring of this volume I am perfectly satisfied; it has all been done 

 under my direction, and from life, with the exception of the Phrynosoma orbicu- 

 lare — the only individual of this species that I have seen was brought from Texas 

 by A. Gaillard, Esq. — the Phrynosoma Douglassii, and the Phrynosoma coronata; 

 but for the correctness of the latter I can answer on the authority of Mr. Nuttall, 

 who has observed them in their native country. 



The genus Hylodes of Fitzinger has only been provisionally adopted, because 

 the animals referred to it could not be arranged with the frogs. There is no 

 occasion to add a new genus to a list already too long, unless further anatomical 

 investigation shall show it to be absolutely necessary. 



Unfortunately I never had an opportunity of seeing the work of Wiegmann, 

 and my quotations from it are through Dumeuil and Bibron, and Blainville; by 

 an error of the press his name is spelt Weigmann. 



