"Nurse, I know what they are," said Lady Mary; "last year I was playing in
the green meadow, and I found a piece of granite with several of these
satin cases. I called them silk pies, for they looked like tiny mince-pies.
I tried to pick one off, but it stuck so hard that I could not; so I asked
the gardener to lend me his knife, and when I raised the crust, it had a
little rim under the top, and I slipped the knife in, and what do you think
I saw? The pie was full of tiny black shining spiders, and they ran out,
such a number of them,--more than I could count, they ran so fast. I was
sorry I opened the crust, for it was a cold, cold day, and the little
spiders must have been frozen out of their warm air-tight house."

"They are able to bear a great deal of cold, Lady Mary--all insects can;
and even when frozen hard, so that they will break if any one tries to
bend them, yet when spring comes again to warm them, they revive, and are
as full of life as ever. Caterpillars thus frozen will become butterflies
in due time. Spiders, and many other creatures, lie torpid during the
winter, and then revive in the same way as dormice, bears, and marmots do."

"Nurse, please will you tell me something about tortoises and
porcupines?" said Lady Mary.

"I cannot tell you a great deal about the tortoise, my dear," replied her
nurse. "I have seen them sometimes on the shores of the lakes, and once or
twice I have met with the small land-tortoise, in the woods on the banks of
the Otonabee river. The shell that covers these reptiles is black and
yellow, divided into squares--those which I saw were about the size of my
two hands. They are very harmless creatures, living chiefly on roots and
bitter herbs: perhaps they eat insects as well. They lie buried in the sand
during the long winters, in a torpid state: they lay a number of eggs,