were
no saw-mills on the stream to send a flood of fungus-breeding sawdust
down with the current. And in spite of all the misfortunes and disasters
to which trout eggs are liable, a goodly number of them were doing quite
as well as could be expected. I suppose one could hardly say that they
were being incubated, for, according to the dictionaries, to incubate is
to sit upon, and certainly there was no one sitting on them. Their
mothers had not come near them since the day they were laid. But the
gravel hid them from the eyes of egg-eating fishes and musk-rats; the
water kept them cold, but not too cold; the fresh oxygen came and
encouraged them if ever they grew tired and dull, and so the good work
went on.

Through each thin, leathery, semi-transparent shell you could have seen,
if you had examined it closely, a pair of bright, beady eyes, and a dark
little thread of a backbone that was always curled up like a horseshoe
because there wasn't room for it to lie straight. But along the outside
of the curve of each spinal column a set of the tiniest and daintiest
muscles was getting ready for a long pull, and a strong pull, and a pull
all together. And one day, late in the winter, when the woods were just
beginning to think about spring, the muscles in one particular egg
tugged with all their little might, the backbone straightened with a
great effort, the shell was ripped open, and the tail of a brand-new
brook trout thrust itself out into the water and wiggled pathetically.

But his head and shoulders were still inside, and for a while it looked
as if he would never get them free. His tail was shaped somewhat like a
paddle set on edge, for a long, narrow fin ran from the middle of his
back clear around the end of it and forward again on the under side of
his body, and with this for an oar he struggled and writhed and
squirmed, and went bumping blindly about among the pebbles like a kitten
with its head in the cream pitcher. And at last, with the most vigorous
squirm and wriggle of all, he backed clear of the shell in which he had
lain for so many weeks and months, and, weak and weary from his
exertions, lay down on a stone to rest.

He had to lie on his side, for attached to his breast was a large,
round, transparent sac which looked very much like the egg out of which
he had just come. In fact it really was the egg, or at least a portion
of it, for it held a large part of what had been the yolk. If you could
have ex