in restraining the excessive
development of certain slugs and insects. The tortoises and turtles
contain a number of species which are edible, and many of the forms
invite the breeder's care. It is, however, when we ascend in the type of
vertebrates to the level of the birds that we find the great array of
creatures which are worth considering as members of our civilization.

Nearly all the birds except those of prey and those which haunt the
seas can easily be accustomed to man. A few of these species which
have been reduced to captivity have not become sufficiently reconciled
to the unnatural conditions to maintain their breeding habits. Even in
these cases, however, it seems likely that in spacious aviaries, at
least in climates to which they are accustomed, it will be possible to
secure the continuous reproduction of the kind, on which all
development by the breeder's art depends.

The ease with which most birds, except those of prey, may be reduced to
domestication is due to the remarkable intensity of their sympathetic
motives. In this regard the class is much more advanced than that of the
mammalia to which we ourselves belong. Accustomed as they are to
ceaseless and active intercourse with each other by means of their
varied calls, largely endowed with the faculty of attention, and
provided with fairly retentive memories, the birds are, on the average,
nearer in the qualities of their intelligence to man than are many of
the species in his own class. It was long ago remarked that the birds of
remote islands, such as the Galapagos, which had never seen man, were at
first not in the least afraid of him. It required, however, but a few
generations of experience to show these creatures that the unfeathered
biped was a singularly dangerous animal, and they at once and
permanently adopted the habit of avoiding him. This incident of itself
shows how quick birds are to learn certain large and important lessons.
We see also the reverse of this education in fear in the rapid way in
which birds become tame when they are secured from persecution. Wherever
shooting is stopped over a considerable territory the birds rapidly
become more tolerant of man's presence. Even among migratory species the
individuals appear to learn that certain places where they are
protected may be resorted to with safety.

Because of their freedom of flight it is in all cases difficult to
bring our perching birds into such relations with the domi