24 The American Naturalist. - [January, 
To what degree this sense of sounds is developed or exists, 
can be learned only by experiment, and requires on the part of 
the experimenter what I unfortunately do not possess,—a knowl- 
edge of music, and the ability to play upon one or more instru- 
ments. 
The sense of sounds, we may assume, varies in animals below 
man as it does in man, or as the color sense varies ; often 
limited, or nearly or quite wanting ; hence the term color-blind- 
ness, and we may use the term sound-deafness in an analagous 
way. 
The experiments of Lubbock referred to show a great differ- 
ence in the perceptions and receptivity of dogs, as between his 
black poodle “ Van ” and Mrs. Lubbock’s collie “ Patience.” In 
speaking of it Sir John says, “I was rather disappointed at this, 
as if it had succeeded the plan would have opened out many in- 
teresting lines of inquiry. Still, in such a case one ought not 
to wish for one result more than another, as of course the object 
of all such experiments is merely to elicit the truth, and our re- 
sult in the present case, though negative, is very interesting.” 
To the terms music and musical sounds, in this connection, 
an exceedingly liberal definition must be conceded,—liberal in a 
simple and non-technical sense, so as to include: | 
1. Sounds not even musical, but occurring in simple rhythmic 
order or succession, like the common marching drum-taps, when 
the full military band is resting. 
2. Melodious sounds, or sounds in themselves musical, occur- 
ring in harmonious sequence. 
3- The same in various strains or keys, more or less complex, 
but combined and arranged in accordance with harmony. 
Of these definitions the first will oftenest serve the purpose. 
It would seem that in the selection of tunes or sounds for ex- 
perimental use, a hint may be had from the animals by observ- 
ing the special sounds uttered by them in their various 
moods 
With the birds, for instance, a tune or sounds which include 
the notes uttered in their amorous moods at or about mating- 
time. 
