56 REPTILES AND BATRACHIANS 



possessing a well-developed expansion on each side of the 

 body, which is supposed to be of use to the creatures in 

 parachuting from one tree trunk to another. Annandale, 

 however, is of the opinion that the use of the structure 

 is not to support the lizard in the air, but to assist in 

 concealing itself by causing it to fit better into its sur- 

 roundings, and thus to be less conspicuous than it would 

 be if its body cast a shadow beneath it. 



The genus is represented by two species, P. homalo- 

 cephalum and P. horsfiddii. In both the limbs and sides 

 of the head, in addition to the sides of the body, are pro- 

 vided with a much-developed membranous expansion. 

 Cantor, who has kept the former species in captivity, says 

 that it has the power of changing rapidly from a very 

 pale to an almost black tint. 



The genus Gymnodactylus, with a distribution which 

 embraces South Europe, Asia, Australia, and South 

 America, has the digits undilated. 



In the Naked-toed Gecko, G. miluisii, of the arid 

 sandy districts of Eastern and Southern Australia, the 

 tail is much swollen, being nearly as broad as the body. 

 Unlike other Geckos, this species, when in progression, 

 bends and raises its body free from the ground, after the 

 manner of a kitten, as the reader may observe from the 

 photograph, showing the creature in this strange attitude. 



The family Uroplatid^, of Madagascar, containing a 

 single genus, Uroplates, combines with a geckoid structure 

 a peculiar sternal apparatus. 



The Bark Gecko, U.Jimbriatus, so called on account of 

 its protective resemblance to the bark of the trees on which 

 it is found, has quite a short tail, which is surrounded by 



