REPTILES. 3 



This is one of the most beautiful species of the genus. The general form is robust and 

 solid, forming a remarkable contrast with most other species of the genus. The surface is 

 beautifully relieved by the fine, large and prominent scales, which are ranged in rows of 

 perfect regularity, of which there are about eighteen on the back and side. 



In colour and markings the individuals differ considerably ; so as to have given rise to the 

 opinion that they form three distinct species. Monsieur Bibron mentions two principal 

 varieties, constituting the Tropidurus olivaceus and Tr. Chilensis of Weigmann. In the former, 

 the colour is of a more or less bronzed bright green, or yellowish, according as the green or 

 yellow colour prevails on the scales, each of which is green, with a border of yellow on each side : 

 this border, according to M. Bibron, in some individuals of a blood-red colour. In some, 

 especially in young individuals, there are several waved bands running transversely across the 

 back. 



In the second variety, says M. Bibron, the upper parts are either of an olive colour, with 

 a golden glance in certain lights, or fulvous, with more or less of a yellow tint ; and these have 

 always four brown bands running the length of the body, appearing as if formed of a series of 

 large spots united together. " The temples are marked with a black line, which extends from 

 the posterior angle of the eye to the ear; another divides behind the occiput into two branches, 

 which pass to the neck there to join the dorsal bands." There are other variations of colour, 

 but scarcely deserving to be considered as constituting permanent or fixed varieties; the 

 largest and finest specimen I have seen, which I received from Chile, is almost uniformly of a 

 fine metallic green, without any markings. 



DIMENSIONS. 



Inches. Lines. 



Length of the head 9 



ofthebody 3 5 



of the tail 6 



Total length 10 4 



Length of anterior extremity 2 



of posterior extremity 1 2 



This species would appear to be very common in Chile, from the numerous 

 specimens from that country in the museum in Paris, which were brought by 

 M. Gay, and by M. D'Orbigny. I have also received specimens from Capt. 

 King. I find only one or two specimens in Mr. Darwin's collection, which he 

 found at Guasco in Chile. 



