A Wave of Life, 61 '
I kept an armadillo at this time, and good cheer and the sedentary life he led in captivity made him excessively fat; but the mousing exploits of even this individual were most interesting. Occasionally I took him into the fields to give him a taste of liberty, though at such times I always took the precaution to keep hold of a cord fastened to one of his hind legs; for as often as he came to a kennel of one of his wild fellows, he would attempt to escape into it. He invariably travelled with an ungainly trotting gait, carrying his nose, beagle-like, close to the ground. His sense of smell was exceedingly acute, and when near his prey he became agitated, and quickened his motions, pausing frequently to sniff the earth, till, discovering the exact spot where the mouse lurked, he would stop and creep cautiously to it; then, after slowly raising himself to a sitting posture, spring suddenly forwards, throwing his body like a trap over the mouse, or nest of mice, concealed beneath the grass.
A curious instance of intelligence in a cat was brought to my notice at this time by one of my neighbours, a native. His children had made the discovery that some excitement and fun was to be had by placing a long hollow stalk of the giant thistle with a mouse in it--and every hollow stalk at this time had one for a tenant--before a cat, and then watching her movements. Smelling her prey, she would spring at one end of the stalk--the end towards which the mouse would be moving at the same time, but would catch nothing, for the mouse, instead of running out, would turn back to run to the other end; whereupon the cat, all excitement,
62 The Naturalist in La Plata,
would jump there to seize it; and so the contest would continue for a long time, an exhibition of the cleverness and the stupidity of instinct, both of the pursuer and the pursued. There were several cats at the house, and all acted in the same way except one. When a stalk was placed before this cat, instead of becoming excited like the others, it went quickly to one end and smelt' at the opening, then, satisfied that its prey was inside, it deliberately bit a long piece out of the stalk with its teeth, then another strip, and so on progressively, until the entire stick had been opened up to within six or eight inches of the further end, when the mouse came out and was caught. Every stalk placed before this cat was demolished in the same businesslike way; but the other cats, though they were made to look on while the stick was being broken up by their fellow, could never learn the trick.
In the autumn of the year countless numbers of storks (Ciconia maguari) and of short-eared owls (Otus brachyotus) made their appearance. They had also come to assist at the general feast.
Remembering the opinion of Mr. E. Newman, quoted by Darwin, that two-thirds of the humble bees in England are annually destroyed by mice, I determined to continue observing these insects, in order to ascertain whether the same thing occurred on the pampas. I carefully revisited all the nests I had found, and was amazed at the rapid disappearance of all the bees. I was quite convinced that the mice had devoured or driven them out, for the weather was still warm, and flowers and fruit on which humble bees feed were very abundant.
A Wave of Life. 63