There has been no hesitation, no trial excavations which have nearly discovered the object of search.

This is proved by the surface of the soil, which is everywhere just as I left it when smoothing it down.

The insect could not make more directly for the objective if guided by the sense of sight; it digs always at the foot of the straw, my private sign.

The truffle-dog, sniffing the ground in search of truffles, hardly attains this degree of precision.
Does the _Hydnocystis_ possess a very keen odour, such as we should expect to give an unmistakable warning to the senses of the consumer?
By no means.

To our own sense of smell it is a neutral sort of object, with no appreciable scent whatever.