glories of the Christmas goose,
the excellent man lent himself generously to my designs.

It was agreed between us that the dog should act according to his own
instincts, receiving the customary reward, after each discovery, no
matter what its size, of a crust of bread the size of a finger-nail.
Every spot scratched by his paw should be excavated, and the object
indicated was to be extracted without reference to its marketable value.
In no case was the experience of the master to intervene in order to
divert the dog from a spot where the general aspect of things indicated
that no commercial results need be expected, for I was more concerned
with the miserable specimens unfit for the market than with the choice
specimens, though of course the latter were welcomed.

Thus conducted, this subterranean botanising was extremely fruitful.
With that perspicacious nose of his the dog obtained for me both large
and small, fresh and putrid, odorous and inodorous, fragrant and
offensive. I was amazed at my collection, which comprised the greater
number of the hypogenous fungi of the neighbourhood.

What a variety of structure, and above all of odour, the primordial
quality in this question of scent! There were some that had no
appreciable scent beyond a vague fungoid flavour, more or less common to
all. Others smelt of turnips, of sour cabbage; some were fetid,
sufficiently so to make the house of the collector noisome. Only the
true truffle possessed the aroma dear to epicures. If odour, as we
understand it, is the dog's only guide, how does he manage to follow
that guide amidst all these totally different odours? Is he warned of
the contents of the subsoil by a general emanation, by that fungoid
effluvium common to all the species? Thus a somewhat embarrassing
question arises.

I paid special attention to the ordinary toadstools and mushrooms, which
announced their near advent by cracking the surface of the soil. Now
these points, where my eyes divined the cryptogam pushing back the soil
with its button-like heads, these points, where the ordinary fungoid
odour was certainly very pronounced, were never selected by the dog. He
passed them disdainfully, without a sniff, without a stroke of the paw.
Yet the fungi were underground, and their odour was similar to that I
have already referred to.

I came back from my outings with the conviction that the truffle-finding
nose has some better guide than odour such as we with our sen