The Nature Library 
ment of the young of some birds carried away by the parents, 
while with others it is voided from the nest? Among certain 
of our birds the family relation, more or less marked, is kept up 
a long time after the young have left the nest. One sees the 
parent birds and the young going about in loose flocks often 
till late into the fall. Of what birds is this true P 
The questions I have suggested are not important; they do 
not hold the key to any great storehouse of natural knowledge. 
Their only value is as a means to quicken the powers of observa- 
tion. We see vaguely, diffusely. Concentrate the attention— 
not to the extent of missing total effects, as the specialist so often 
does, but for the purpose of reading correctly the play of life that 
is constantly going about us. 
Nature’s book is like any other book: you must open the 
covers; you must fix your eyes upon the text; you must get into 
the spirit of it. When you have read one sentence correctly you 
are so much the better prepared to read the next one. 
A world of nature about us that we are quite apt to be 
oblivious to, except as it results in our annoyance, is the insect 
world. We do not take an intelligent interest in the ants, or the 
bees, or the moths, or the butterflies, yet here is a field of obser- 
vation that will amply repay one. One day in a great city I saw 
a butterfly calmly winging its way high above the crowded street. 
I knew it was the monarch (Anosia plexippus), probably the 
greatest traveler of all our butterflies. It is quite certain that they 
migrate to the South in the fall, and that many return in the 
spring. I learn from Mr. Holland’s Butterfly Book in this library 
that they have even crossed both oceans—of course, by 
catching a ride on vessels—and are now found in Australia and 
in the Philippines, and they have been collected in England. 
Have you not seen its chrysalis suspended from some weed or 
bush, looking like the trunk from some tiny warrior encased in 
pale-green armor, riveted with gold-headed rivets, a broad, heavy 
shield over the abdomen, and plate upon plate over the shoulders 
and back? It is a milkweed butterfly, and will serve as a good 
introduction to this new world of winged life. Early last spring 
I found upon the window of my cabin in the woods a butterfly 
that had evidently hybernated in some snug crack or corner of 
the building. This was the mourning cloak, with me the first 
vernal butterfly. When one sees this butterfly dancing through 
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