Bramble-bees and Others 



one more: their wonderful poison, the 

 strength of which is regulated by delicate 

 doses. The Bee revenging herself intensifies 

 the virulence of her poison ; the Sphex putting 

 her grubs' provender to sleep weakens it, re- 

 duces it to what is strictly necessary. 



One more instance of nearly the same kind. 

 I prefer to take my subjects from among the 

 Orthoptera, who, owing to their imposing size 

 and the thinness of their skin at the points 

 to be attacked, lend themselves better than 

 other insects to my delicate manipulations. 

 The armour of a Buprestis-beetle, the fat 

 blubber of a Rosechafer-grub, the contortions 

 of a Caterpillar present almost insuperable 

 obstacles to the success of a sting which it is 

 not In my power to direct. The insect which 

 I now offer to the Bee's lancet is the Great 

 Green Grasshopper (Locusta viridissima) , 

 the adult female. The prick is given in the 

 median line of the fore-legs. 



The effect is overwhelming. For two or 

 three seconds, the insect writhes in convulsions 

 and then falls on its side, motionless through- 

 out, save in the ovipositor and the antennas. 

 Nothing stirs so long as the creature is left 

 alone; but, if I tickle It with a hair-pencil, 



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