270 THE BOOK OF A NATURALIST 
surpassed all other creatures in human-like feelings; 
our periodicals would teem with anecdotes of its 
marvellous intelligence; innumerable books would 
be written on the subject, and the psychological 
biologists would put it next to man in their systems, 
one step below him on the throne of life, and far 
above the general herd of animals. 
It is a fact, that might well stagger belief in the 
dog’s superior intellect, that mammalians so low 
down as rats and mice when properly treated and 
trained make attached and intelligent pets; and 
that a mouse, or a sparrow, or a snake, or even a 
creature so small and far down in the organic scale 
as a flea, may be taught, without very great diffi- 
culty, to perform tricks which, if performed by a 
dog, would be pronounced very clever indeed. 
Most people who witness the pretty performances 
of small mammals, birds and insects—which are 
usually up to the level of the dog’s performances 
seen at the music-halls—probably think, if they 
think anything at all about the matter, that the 
exhibitor in such cases is the possessor of a mysteri- 
ous kind of talent by means of which he is able to 
make these small creatures come for a few moments 
out of the instinctive groove they move in to do 
the things he wishes, much as little toy ducks and 
swans, which are hollow inside, are made to swim 
round in a basin of water after a stick of loadstone; 
only in the case of the exhibitor of animals the 
loadstone is hidden from the spectators. His 
trick, or mysterious talent, consists in the know- 
