46 SOCIAL LIFE IN THE INSECT WORLD 



found have been laid upon twigs of the Spartium 

 junceuntf which are Hke straws stuffed with pith, and 

 especially on the upper twigs of the Asphodelus cerasiferiis, 

 which rises nearly a yard from the ground before 

 ramifying. 



It is essential that the support, no matter what its 

 nature, should be dead and perfectly dry. 



The first operation performed by the Cigale consists in 

 making a series of slight lacerations, such as one might 

 make with the point of a pin, which, if plunged obliquely 

 downwards into the twig, would tear the woody fibres 

 and would compress them so as to form a slight pro- 

 tuberance. 



If the twig is irregular in shape, or if several Cigales 

 have been working successively at the same point, the 

 distribution of the punctures is confused ; the eye wanders, 

 incapable of recognising the order of their succession or 

 the work of the individual. One characteristic is always 

 present, namely, the oblique direction of the woody 

 fragment which is raised by the perforation, showing 

 that the Cigale always works in an upright position and 

 plunges its rostrum downwards in the direction of the 

 twig. 



If the twig is regular, smooth, and conveniently long 

 the perforations are almost equidistant and lie very 

 nearly in a straight line. Their number varies ; it is 

 small when the mother, disturbed in her operations, 

 has flown away to continue her work elsewhere ; but 

 they number thirty or forty, more or less, w^hen they 

 contain the whole of her eggs. 



Each one of the perforations is the entrance to an 

 obUque tunnel, which is bored in the medullary sheath 



