[34] Consult Romanes, Animal Intelligence, p. 26.
CHAPTER III
MEMORY
In discussing memory as it is to be observed in the lower animals, I think it best to divide the subject into four parts; viz., Memory of Locality (Surroundings), Memory of Friends (Kindred), Memory of Strangers (Other Animals not Kin), and Memory of Events (Education, Happenings, etc.).
Memory of Locality.—There can be no doubt but that the rhizopods observed by Carter displayed memory of locality. He distinctly asserts that he saw the actinophrys, after it had incepted a starch grain, "crawl away to a good distance" and then return to the spore-cell from which it was taking the grains of starch. The creature must have remembered the route to and from the spore-cell. The same must be said of the water-louse observed by myself, which not only came back to the source of its food-supply, but also returned to a certain lurking-spot at which it hid itself each time until it had eaten the hydra buds. It must be remembered that a journey of one inch, to these minute little creatures, is, comparatively speaking, an immense distance. Each grain of sand, each particle of decayed vegetable matter, etc., is, to these microscopic animalcules, a gigantic boulder, a mighty muck heap. These obstacles in the path undoubtedly serve as landmarks to the wandering myriads of microscopic animalcules.
It can be demonstrated that the snail has memory of locality. This creature is essentially a homing animal, as I will show in the chapter on Auxiliary Senses, consequently we would naturally expect to find it possessing memory of locality. An interesting observation by Mr. Lonsdale, an English observer, which has been often quoted, clearly proves that this creature does possess this psychical function. Mr. Lonsdale placed two snails in a small and badly kept garden. One of them was weak and poorly nourished, the other strong and well. The strong one disappeared and was traced by its slimy track over a wall into a neighboring garden where there was plenty of food. Mr. Lonsdale thought that it had deserted its mate, but it subsequently appeared and conducted its comrade over the wall into the bountiful food-supply of the neighboring garden. It seemed to coax and assist its feeble companion when it lingered on the way.[35]
Marked bees and ants invariably return to places where they have found food-supplies, thus showing the possession of a memory of locality and route. It is very interesting to watch a marked ant during her journey back to her nest, after she has been carried away and placed among unfamiliar scenes and surroundings. At first, owing to her fright, she will dash away helter-skelter; but soon recovering, she will head in the direction of home, and moderate her pace until she creeps along at a very cautious and circumspect gait, indeed. Every now and then she will climb a tall grass-blade or weed and take observations. After a while she sees certain landmarks, and her speed becomes faster; soon the surrounding country becomes familiar, and she ceases to climb blades of grass, etc., now she is in the midst of well-known scenes, and at last she fairly races into her nest.
In this instance the ant is led at first by her sense of direction alone; as soon, however, as she comes to country which she has hunted over, and with which she is familiar, memory comes into play and the sense of direction ceases to act, or, if it acts at all, it acts unconsciously.