The Sense of Smell 



is seeking, the rabassier cannot guess the 

 presence of the truffle, which ripens in winter 

 underground, at a depth of eighteen inches or 

 so; he needs the aid of the Dog or the Pig, 

 whose scent pries into the secrets of the soil. 

 Well, these secrets are known to different in- 

 sects even better than to our two helpers. In 

 order to discover the tuber on which their 

 family of grubs is to be fed, they possess a 

 scent of exceptional perfection. 



Long ago, from truffles dug up spoilt and 

 teeming with vermin and placed in this con- 

 dition in a glass jar with a layer of fresh sand, 

 I obtained first a small red Beetle (Anisotoma 

 clnnamornea, PANZ.) and then various Dip- 

 tera, including a Sapromyzon, who, with her 

 sluggish flight and feeble frame, reminds me 

 of a Fly, clad in yellow velvet, known as 

 Scatophaga scybalana, that placid frequenter 

 of human excrement in autumn. 



The latter finds her truffle on the surface 

 of the ground, at the foot of a wall or hedge, 

 man's usual hasty refuge in the country; but 

 how does the other know at w r hat point un- 

 derground lies hers, or rather her grubs' 

 truffle? To go down and hunt about in the 

 depths is beyond her power. Her frail 



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