l60 CLASSIFICATION OF REPTILES. 



horny points : the eyes are very small^ and the tym- 

 panum completely covered by the external skin : the 

 lungs are unequal^ as in the generality of serpents, one 

 being large, the other very small. 



(164.) The last family we have named the Agamid^, 

 or frog-lizards, thereby intending to denote the fat- 

 bodied groups of which the orbicular lizards of Cuvier 

 form the type (^PlD'ynosomaVi a.glei-). Hitherto, how- 

 ever, they have never been thus designated j and not 

 having personally examined several of the sub-genera, 

 we have not been able to give the contents of this group 

 that degree of finish which hereafter we hope to ac- 

 comphsh. Generally speaking, they are mostly short- 

 tailed depressed hzards, with large bellies, narrow necks, 

 and widened heads, so as to resemble, in a great measure, 

 some of the Iguaxid^e ; they have not, however, the 

 palatine teeth which distinguish Iguana, or the broad 

 spiny-ringed tails of Stellio. . Some few of the sub- 

 genera, indeed (forming the genus Lophyura Gray), 

 have spiny crests upon the back and tail, but we feel 

 by no means sure that these should not be transferred 

 to the Iguanidce, near to Brachycephahis. Certain it 

 is, however, that there is a decided affinity between the 

 skinks, or the Scixcoid^, and Tropidurus Wieg.* This 

 being admitted, we have next to ascertain if any, and 

 what, lizards evince an affinity with the chameleons, 

 because it is to that family that, in a circular course, 

 we are to return. Now there can be no question that 

 this affinity is shown in the sub-genus Lyriocejjhalus, 

 where we have the head and the peculiar telescopic eyes 

 of the chameleon, joined to the body, covered with im- 

 bricate scales of an Agami. Our only remaining dif- 

 ficulty, therefore, is to trace the connection between 

 these two extreme groups : this we have endeavoui'ed to 



* MM. Dumeril and Bibron have observed regarding Mr. Gray's genus 

 Leiocephalus : "Ilsont avec les Scinques une certaine ressemblance que 

 nous alions trouver complete dans les premieres espdces du genre suivant 

 celles qui foment le groupe des Pructrotrupes Leiodhres {Tropidurus 

 Wieg.;."' ErpetoL Gen. ten. iv. p. 260. 



