120 REPTILES OF THE WORLD 



ferent species; D. everetti has the central appendage 

 short and blunt, while D. quinquef asciatus has an ex- 

 tremely slender, veritable hanging comb, which is really 

 a third as long as the body. D. volans seems to be the 

 commonest species. The body is lustrous gray or green- 

 ish with dark wavy cross-bands and spots. The wing 

 membranes are brilliant orange, on which, in striking 

 contrast, are blotches or bands of black. With the male, 

 the throat appendage is orange; that of the female is 

 blue. 



Calotes, with nineteen species, is an interesting genus, 

 not from any marked structural development, but from 

 the habit of its members of rapidly changing their col- 

 ors. The species have coarse, rough scales and an ex- 

 tremely long, slender tail. Many have a crest of very 

 sharp spines on the forward part of the body or on the 

 head. Several of the species reach a length of two feet. 

 Their habitat covers India, southern China and Ma- 

 laysia; throughout these regions they are among the 

 most abundant of lacertilians. They are typical tree 

 lizards and mostly insectivorous. 



The "Bloodsucker," Calotes versicolor, one of the 

 commonest lizards of continental India, derives its name 

 from an altogether harmless trait. When the lizard is 

 excited or angered, the brownish body turns yellow, while 

 the sides of the head, the throat and the neck become 

 brilliant red. This, however, is merely one of the 

 numerous color variations. Broad, dark bands are 

 often visible on the back, these broken by a central stripe 

 of straw-color; this coloration may give way to a rich, 

 uniform cinnamon, thence to a funereal black. The 

 most startling changes of color occur among the males 

 during the breeding season, when the members of this 

 sex engage in frequent fights. 



