The migrations among the four-footed animals that sometimes occur over a large, part of the country--among the rats, the gray squirrels, the reindeer of the north--seem to be of a similar character. How does every individual come to share in the common purpose? An army of men attempting to move without leaders and without a written or spoken language becomes a disorganized mob. Not so the animals. There seems to be a community of mind among them in a sense that there is not among men. The pressure of great danger seems to develop in a degree this community of mind and feeling among men. Under strong excitement we revert more or less to the animal state, and are ruled by instinct. It may well be that telepathy--the power to project one's mental or emotional state so as to impress a friend at a distance--is a power which we have carried over from our remote animal ancestors. However this may be, it is certain that the sensitiveness of birds and quadrupeds to the condition of one another, their sense of a common danger, of food supplies, of the direction of home under all circumstances, point to the possession of a power which is only rudimentary in us. Some observers explain these things on the theory that the flocks of birds have leaders, and that their surprising evolutions are guided by calls or signals from these leaders, too quick or too fine for our eyes or ears to catch. I suppose they would explain the movements of the schools of fish and the simultaneous movements of a large number of land animals on the same theory. I cannot accept this explanation. It is harder for me to believe that a flock of birds has a code of calls or signals for all its evolutions--now right, now left, now mount, now swoop--which each individual understands on the instant, or that the hosts of the wild pigeons had their captains and signals, than to believe that out of the flocking instinct there has grown some other instinct or faculty, less understood, but equally potent, that puts all the members of a flock in such complete rapport with one another that the purpose and the desire of one become the purpose and the desire of all. There is nothing in this state of things analogous to a military organization. The relation among the members of the flock is rather that of creatures sharing spontaneously the same subconscious or psychic state, and acted upon by the same hidden influence, in a way and to a degree that never occur among men. The faculty or power by which animals find the way home over or across long stretches of country is quite as mysterious and incomprehensible to us as the spirit of the flock to which I refer. A hive of bees evidently has a collective purpose and plan that does not emanate from any single individual or group of individuals, and which is understood by all without outward communication.