116 TROPICAL NATURE, AND OTHER ESSAYS. 



Frogs and Toads. The only Amphibia that often 

 meet the traveller's eye in equatorial countries are the 

 various kinds of frogs and toads, and especially the 

 elegant tree-frogs. When the rainy season begins, and 

 dried-up pools and ditches become filled with water, 

 there is a strange nightly concert produced by the frogs, 

 some of which croak, others bellow, while many have 

 clanging, or chirruping, and not unmusical notes. In 

 roads and gardens one occasionally meets huge toads six 

 or seven inches long ; but the most abundant and most 

 interesting of the tribe are those adapted for an arboreal 

 life, and hence called tree-frogs. Their toes terminate 

 in discs, by means of which they can cling firmly to 

 leaves and stems. The majority of them are green or 

 brown, and these usually feed at night, sitting quietly 

 during the day so as to be almost invisible, owing to 

 their colour and their moist shining skins so closely re- 

 sembling vegetable surfaces. Many are beautifully marbled 

 and spotted, and when sitting on leaves resemble large 

 beetles more than frogs, while others are adorned with 

 bright and staring colours ; and these, as Mr. Belt has 

 discovered, have nauseous secretions which render them 

 uneatable, so that they have no need to conceal them- 

 selves. Some of these are bright blue, others are 

 adorned with yellow stripes, or have a red body with 

 blue legs. Of the smaller tree-frogs of the tropics 

 there must be hundreds of species still unknown to 

 naturalists. 



Mammals Monkeys. The highest class of animals, 

 the Mammalia, although sufficiently abundant in all 

 equatorial lands, are those which are least seen by the 

 traveller. There is, in fact, only one group the 



