BEIMSTONE MOTH. 147 



One of the examples of animal life simulating vege- 

 tation now comes before us in the person of the 

 Brimstone Moth, or rather its caterpillar. 



This is a very common insect, and may be recog- 

 nised at once by its portrait on plate C, fig. 3. 



The caterpillar is represented immediately above, 

 fig. 3 a. This is one of the caterpillars called 

 " Loopers," on account of their peculiar mode of 

 walking. 



They have no legs on the middle portion of their 

 bodies, but only the usual six little legs at the three 

 rings nearest the head, and a few false legs by the 

 tail ; so when they want to walk, they attain their 

 object by holding fast with their false or pro-legs as 

 they are called, and stretching themselves forward to 

 their fullest extent. The real legs then take their 

 hold, and the pro-legs are drawn up to them, thus 

 making the creature put up its back like an angry 

 cat. 



The grasp of the pro-legs is wonderfully powerful, 

 and in them lies the chief peculiarity of the creature 

 The surface of the body is of a brownish tint, just 

 resembling that of the little twigs on which it sits ; 

 there are rings and lines on its surface that simulate 

 the cracks and irregularities of the bark, and in one 

 or two places it is furnished with sham thorns. 



Trusting in its mask, the caterpillar grasps the 

 twig firmly, stretches out its body to its full length, 

 and so remains, rigid and immovable as the twigs 



