582 Change of Colour in Lizards. 



ing : but I do not observe that the outline of the Anolidae is at 

 all altered, however great may be the varying of the tints. 



The number of a green species of AncMis (i^acerta bullaris 

 Z>., from its throat being sujjposed to be inflated into a ball: 

 the Anolis variabilis Guild.^ variable) is, in some of our 

 islands perfectly incredible, and one only wonders that the 

 race of insects is not extinct. Indeed, one never sees here 

 moths and other objects settling on walls and trees, as in 

 England : from the danger of such exposure, it often happens 

 that insects whose larvae are readily obtained for breeding are 

 never taken in a state of liberty. 



On large trees whole families of lizards are actively employed 

 in their insect chase, while every rock, fence, or smaller tree, 

 has one at least resting in readiness for its prey, or jumping 

 from spray to spray with its sucker-bearing toes. Yet few 

 will be found alike in colouring, though there are some toler- 

 ably permanent varieties. The general unassumed colour is a 

 lively yellowish green : yet this is varied at will, and changed 

 to grey, dark dirty brownish green, or is curiously varied. 

 The aspect of each individual is adapted admirably to the spot 

 it chooses as a cruising ground, which it commonly retains, 

 unless disturbed, for very long periods ; a fact which is easily 

 determined by the notice of mutilated individuals. 



But, whatever may be the assumed colouring of the indi- 

 vidual, place it in confinement, and its mask is withdrawn as 

 if by magic, and the bright green of nature is restored. 



If a dark mass of volcanic trap [rock] is selected for a 

 -cruising station, the darkest colour is adopted : if the light 

 foliage of trees and plants is preferred, a tint is acquired 

 resembling its resting-place, and calculated for concealment 

 and deception. 



[In another place, Mr. Guilding has noted thus ; in relation 

 to the remarks, in II. 469., on " the chamaeleon's antipathy 

 to black :'* — Many of our lizards reside constantly on the 

 darkest rocks blackened by the air, and decayed cryptogamic 

 plants : in which case the skin assumes a corresponding tint.] 



In these cases the mute sexes separated from each other 

 would have difficulty in meeting during the season of their 

 loves ; but nature, without enforcing the necessity of their 

 returning to their proper colour, which would betray them to 

 their prey and their enemies, has given to the diurnal species, 

 which alone can need it, a retractile dewlap process, of a light 

 and striking colour, which is never altered ; of larger size in 

 the males, which, with a vertical motion of the head, is often 

 extended into a broad membrane to attract the notice of the 

 other sex, as birds are known to display their plumose and 

 other ornamental appendages for the like object. 



