My First Summer 



day, wherever they can find anything worth 

 while, until they are themselves stung by 

 frost. The large jet-black ants are only 

 ticklish and troublesome when one is lying 

 down under the trees. Noticed a borer 

 drilling a silver fir. Ovipositor about an 

 inch and a half in length, polished and 

 straight like a needle. When not in use, 

 it is folded back in a sheath, which ex- 

 tends straight behind like the legs of a 

 crane in flying. This drilling, I suppose, is 

 to save nest building, and the after care of 

 feeding the young. Who would guess that 

 in the brain of a fly so much knowledge 

 could find lodgment ? How do they know 

 that their eggs will hatch in such holes, 

 or, after they hatch, that the soft, help- 

 less grubs will find the right sort of nour- 

 ishment in silver fir sap? This domestic 

 arrangement calls to mind the curious fam- 

 ily of gallflies. Each species seems to know 

 what kind of plant will respond to the irri- 

 tation or stimulus of the puncture it makes 



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