78 NATURE SKETCHES IN TEMPERATE AMEfiICA 



that he stood over the veins, the legs being arranged almost 

 parallel with them. From this view of his body, he was so 

 closely in accord with the veins that he was almost invisible. 

 I wondered at the time if this position was a mere coincidence 

 or was a common behavior. It is obvious that in this attitude 

 and at a little distance the young walking-stick may stand on 

 the upper surface of the leaves and defy the sharp-eyed birds 

 or other vertebrates to discover his attenuate form. 



While I found this resemblance of the walking-stick to the 

 central and radiating veins of the oak and other leaves to be 

 remarkably perfect, there is another point that I noticed in this 

 connection worthy of consideration. I found that when these 

 Orthoptera become unduly alarmed their usual impulse seems 

 to be to seek the under surface of the leaf. After some study 

 I also found that he is here even more iprotected than when 

 standing on the upper surface, not only on account of the 

 shadows cast on his body, but from the fact that the assimilation 

 is made far more perfect by reason of the median and lateral 

 veins of the leaves being more strongly and roundly in reUef 

 here than they are shown above. I have photographed one of 

 these insects on the underside of the oak leaf just as I found it, 

 that the reader may get a better idea of the remarkable pro- 

 tection afforded by this resemblance to the veins. The resem- 

 blance of the walking-stick to the venation of the oak can be 

 demonstrated in quite a striking manner, if the main median 

 vein with two pairs of laterals are cut out carefully with a 

 pair of scissors. The result is a fair facsimile of the young 

 walking-stick. 



Of course, in the position which the young walking-stick 

 naturally assumes in foraging, it does not always accurately 

 lie over the veins of the leaf, for the veins shghtly alternate. 

 I have found, however, by observations, that if the insect 

 stands at any angle on the leaf, and if he is viewed from below, 

 his resemblance to the veins is sufficient to protect him. The 

 nearer the position of the body corresponds to the central 

 vein structure the greater the safety from attacks. The oak 

 is doubtless the most often chosen as the natural habitat of 

 the common walking-stick, but I have often found the young 

 at home on a variety of herbage, shrubs, and small trees, where 



