WALKING BRANCHES. 287 



themselves out to their fullest length ; then, steadied by the 

 grasp of the fore-feet, bring forward the hind ones to meet 

 them ; thus with every step looping up the body as before. 



In the month of May, or beginning of June, we may often, 

 by careful looking for, find a branch of elder supporting its 

 very image in a caterpillar,* which is perhaps the most re- 

 markable of the above singular family a withered-looking 

 stick-like creature, knobbed and ringed and coloured, and even 

 cracked after the exact pattern of the browner stalks of its 

 native tree. This most perfect simulator, like others of his 

 simulating relatives, aids the deception of his figure by his 

 branch-like attitudes and branch-like quietude (often main- 

 tained from morning till night), at which latter period he 

 mostly prefers to exercise both his jaws and locomotive powers. 

 After the usual changes, this curious caterpillar becomes, about 

 July, a pale sulphur- coloured moth, remarkable for the elegant cut 

 of its angular pinions, of which the hinder pair, being prolonged 

 into acute tails, have given it the name of " Swallow Tail."^ 



When we look at the winged development of this stick - 

 animal (a form of grace and beauty strikingly contrasted with 

 the stiff rigidity of its cast-off covering) we can still trace a 

 resemblance to the siic\.-veyelable } in its likeness to floral pro- 

 ducts, stalk derived. The Brimstone Butterfly, that darling 

 of the spring, has been long noticed for the resemblance of 

 its delicate pinions to the petals of a primrose fluttering in 



* Vignette. f Ourapterix sambucaria. 



