3i8 THE WONDERS OF INSTINCT 



several times to the egg already treated, others by differ- 

 ent mothers. Well, the number of these cocoons varies 

 greatly. Generally, it fluctuates in the neighborhood of 

 twenty, but I have come across as many as sixty-five; 

 and nothing tells me that this is the extreme limit. What 

 hideous industry for the extermination of a Butterfly's 

 progeny ! 



I am fortunate at this moment in having a highly 

 cultured visitor, versed in the profundities of philosophic 

 thought. I make way for him before the apparatus 

 wherein the Microgaster is at work. For an hour and 

 more, standing lens in hand, he, in his turn, looks and 

 sees what I have just seen; he watches the layers who go 

 from one egg to the other, make their choice, draw their 

 slender lancet and prick what the stream of passers-by, 

 one after the other, have already pricked. Thoughtful 

 and a little uneasy, he puts down his lens at last. Never 

 had he been vouchsafed so clear a glimpse as here, in my 

 finger-wide tube, of the masterly brigandage that runs 

 through all life down to that of the very smallest. 



