54 



The Study of Animal Life 



examples of precise resemblance to surrounding objects ; 

 but one of the sea-horses (Phyllopteryx eques) is said to be 

 exceedingly like the seaweed among which it lives. It is 

 very difficult at present to venture suggestions as to the 

 constitutional tendencies which may have resulted in 

 " walking-leaves " and " walking-sticks,'' but forms related 

 to these tend to resemble leaves or sticks sufficiently to deter 



Fig. 7. — Leaf-insect seated on a branch. (From Belt.) 



one from postulating a mere sport as the origin of the 

 peculiarity which distinguishes Phyllium or Phasma. On 

 the other hand, some of the strangely precise minute 

 resemblances may be the fostered results of slight indefinite 

 sports. It is also possible that some of the cleverer 

 animals, such as spiders, learn to hide among the lichens 

 and on the bark which they most resemble. But in every 

 case, and especially where there are many risks, as among 



