THE ALLIES OF THE KED-LEGGED LOCUST 21 



cockroach, or "croton-bug" (Phyllodro'mia german'icd), with 

 its egg-case ; and a larger species, the so-called Oriental 

 cockroach (Stiloyjyga orien'talis), though there is little evi- 

 dence to show its original home. 



Walking-Sticks. The peculiar insects called walking-sticks 

 are also related to the locusts. Among them are some of 

 the most remarkable illustrations of protective resemblance 

 known in the animal kingdom. The common species in the 

 eastern United States (Diapherom 1 'era femora' to) is shown 

 in Fig. 12. The body and legs are elongated to such an 

 extent that when at rest the resemblance to a twig is most 



FIG. 11. Cockroaches. Natural size 



striking. The insect undergoes a seasonal change of color, 

 being brown when first hatched, turning green after feeding, 

 and changing to brown again as the season advances. It has 

 the power of replacing broken appendages at the next molt, 



