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 
along 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 business- 
like'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. EH. 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 disap- 
pearance 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, 
