CHAMELEONS 
the branches or leaves of trees and shrubs may be useful 
in another way — viz. to prevent the flies or other insects 
seeing the danger to which they are exposed in approach- 
ing within reach of its treacherous and sticky tongue. As 
the chameleon cannot follow its prey, it has to wait until 
it comes so near that the tongue will reach it, and every- 
thing that would aid in accomplishing this act is fully in 
accordance with all we know respecting the means pos- 
sessed by other animals in obtaining food ; and the question 
of the usefulness of the change of colour will perhaps for 
ever remain beyond our understanding, like the mode 
itself of changing colour. Many striking instances of 
insects assuming the colour of the situation in which they 
flx themselves in the chrysalis state have been brought to 
notice, they becoming white, red, black, or green, accord- 
ing to their position during their torpid condition. Some 
butterflies and moths have the form and colour of dead 
leaves. The latter are sometimes coloured and marked 
like the bark of trees on which they are found. Some 
caterpillars and insects are in the shape of bits of dead 
stick. All these and other modes of disguise given to 
various classes of animals are no doubt wisely ordained to 
serve a designed end ; so wonderful and perfect do they 
appear that they are beyond human comprehension. The 
change of colour in frogs, especially the “ little green tree- 
frog,” is very noticeable, varying from the most brilliant 
apple-green to nearly jet-black. Toads, and many of the 
lizards, particularly the iguanas of tropical America, are 
all changeable. The latter animals are perhaps quite equal 
to the chameleon in the power of changing colour, but 
they have not received the same amount of notice or 
attention ; the variation being chiefly from the most 
beautiful bright green to a dull, pale brown, both colours 
well adapted to enable the animal to escape unobserved in 
-]97 
