INTEODUCTION. 



This volume contains an account of all the species of Lizards 

 belonging to the families GecJconidce, Euhlepharidce, Uroplaiidce, 

 Pygopodidm, andAgamidtB, of which descriptions have been published. 

 Over three fourths of the species described have been examined by 

 myself. 



The following Table will show the great progress made in our 

 knowledge of species since the publication of the last general works 

 on the subject, viz. Dumeril and Bibron's 'Erpetologie Generale,' 

 vols, iii.-v., 1836-1839, and Gray's first edition of this Catalogue 

 in 1845 :— 



Number of Species characterized 



Families. by Dum. & Bibr. by Gray. in present volume*. 



Geckonidse 53 97 270 



Eublepharidse — 1 7 



Uroplatidee 2 2 3 



Pygopodidse 2 7 8 



Agamidse 50 79 202 



Total.. 107 186 490 



A comparison of the numbers of species and specimens in the 

 K"ational Collection in 1845 and at the present date gives the 

 following result : — 



* Only those species to which I have appended an ordinal number are included 

 in this estimate, without those which are doubtful and merely referred to in 

 footnotes or otherwise. 



