248 ANOURA. HYLAD^. 



is provided with suckers, analogous to those we 

 have noticed in the foot of the Gecko." * Each 

 toe, both of the fore and hind feet, is dilated at 

 the tip into a circular pallette or pad, varying in 

 size in different genera : these little cushions are, 

 it is true, moistened with a glutinous fluid, as 

 is the whole surface of the body ; but we believe 

 that this viscidity is not, as has been supposed, 

 the agent by which the animal so powerfully 

 adheres against gravity ; but that the pallettes 

 act as suckers, being sustained in their position 

 by the pressure of the atmosphere, a vacuum 

 being produced beneath them, or removed at the 

 creature's will. 



The colours of the Tree-frogs are various, and 

 are often brilliant and beautiful ; like many 

 other Reptiles they have the faculty of chang- 

 ing their hues to an extent that often affords 

 them protection, by rendering them difficult to 

 be discerned. They are very numerous in the 

 damp woods of tropical America, residing habitu- 

 ally by day in the concealment afforded by the 

 huge BromeliacecE or Wildpines, and other para- 

 sitical plants that grow in tufts on the trunks 

 and branches of great trees, the sheathing bases 

 of whose leaves not only afford them umbrageous 

 bowers in which to dwell, but also form reser- 

 voirs in w^hich the rain-water collects, and thus 

 provide the moisture without which they would 

 soon expire. The under-surface of the bodies 

 of these arboreal Frogs is very different from 

 that of the terrestrial species ; the skin, instead 

 of being smooth, is covered with granular glands 

 pierced by numerous pores, through which the 

 * " Popular History of Reptiles," 303. 



