480 



JOURNAL -OF ECONOMIC ENTOMOLOGY 



[Vol.3 



TABLE 1 



Wet conditions 



Dry conditions 



Number of eggs hatched 



Specimens which emerged completely 



from the egg-shell 



Specimens unable to emerge completely 



from the egg-shell 



200 



12 



188 



ditions failed, after springing off the operculum, to extract themselves 

 completely from the egg-shell. It is evident from this that dryness 

 has a marked effect upon the complete emergence of the walking-stick 

 from the egg. 



In the next experiment, some of those specimens, which failed to 

 free themselves fully from the egg, were put into a glass jar contain- 

 ing about an inch of wet sand covered with moistened filter paper. 

 Those walking-sticks, which had one or more legs caught within the 

 egg-shell, usually succeeded in withdrawing all the appendages, while 

 those that had all the legs, antennae and abdomen caught, ordinarily 

 failed to free themselves. 



In another experiment, some of the walking-sticks, which failed to 

 extricate themselves completely from the egg, were put into a glass 

 jar under dry conditions. These specimens, without exception, failed 

 to withdraw the parts caught within the egg-capsule and all died 

 with the same parts still held securely within the egg. 



Godelmann^ observed in Bacillus rossi ? that "die jungen Larven 



die Eihiilsen auf die Dornen der Brombeerranken zu stulpen ver- 

 suchten und dann mit den Vorderfiiszen klimmzuartige Bewegungen 

 ausflihrten, um sich zu befreien, wobei nicht selten ein Bein oder 

 mehrere verloren gingen, die dann spater nach der Hautung regener- 

 irt wurden." In only a few cases, have we observed a walking-stick 

 throw off a leg which was caught within the shell-egg. When a 

 specimen, which had one or more legs caught, was put in a glass jar 

 containing a twig from a hazel-nut shrub, the leaves furnished enough 

 moisture by transpiration to allow nearly all of the young walking- 

 sticks to withdraw the appendages. 



The eggs, which still remained unhatched, were now interchanged, 

 the remaining 800 eggs, which had been on the wet sand being trans- 

 ferred to the dry conditions and vice versa. The following table shows 

 the results of the hatching of the next 100 eggs in each case: 



