Citizen Bird: Scenes from Bird-Life in Plain English for Beginners. Elliott Coues
them unless they were classified. To classify is to put things that are most alike closest together, then next nearest them things that are next most alike, and to keep furthest apart those things that are least alike. Now it is true that all beasts, birds, snakes, lizards, frogs, and fishes have some things alike, though each has some other things different from all the rest. If they were not all alike in some things, we could not call them all animals. One of the things in which all the animals I have named are alike is, that they all have skeletons. One of the things in which all their skeletons are alike is, that they have backbones. Backbones are the chains of bones that run along the back from the head to the tail. Backbones are called by the Wise Men vertebrae; animals that have backbones are named Vertebrates; and animals that lack backbones are named Invertebrates."
"Tell us the names of some Invertebrates, please, Doctor," said Rap.
"Well, all sorts of insects are Invertebrates, and so are lobsters and crabs, oysters and clams, worms, starfishes, jelly-fishes, corals, and even sponges. Then there are some too small to see without a microscope. But never mind about Invertebrates now. I only want you to remember that all beasts, birds, reptiles, and fishes are Vertebrates, and that there are five principal classes of them. If I should tell you as much about them as I have about the Building of a Bird, you would see that they are all built on what we call the Vertebrate plan of structure. Here is a chart of the Classes of Vertebrates—you can study it this afternoon, till you learn it by heart."
VERTEBRATES
Animals with Backbones
CLASS I. Mammals.—Warm-blooded animals which have fur or hair, bring forth their young alive, and nurse them. House People are Mammals.
CLASS II. Birds.—Warm-blooded animals which have feathers and lay eggs.
CLASS III. Reptiles.—Cold-blooded animals which have scaly skins, like lizards, snakes, and turtles.
CLASS IV. Batrachians.—Cold-blooded animals which have naked skins, like frogs, toads, and newts.
All the foregoing classes, except a few of the Batrachians, breathe air in lungs, and almost all, except snakes, have legs; none now living can fly, except bats and birds; but bats are Mammals.
CLASS V. Fishes.—Cold-blooded animals which have either scaly or naked skins, but no fur or feathers; which live in the water, breathe it with their gills, and swim in it with fins.
CHAPTER V
CITIZEN BIRD
The apple trees were in full bloom the day that the Doctor again found time to be with the children. It was exactly the kind of a day that birds like. The ground was soft enough to let the earthworms come up to breathe, so that Robins could catch them easily, and the air was full of all kinds of insects newly out from their long winter sleep in their soft cocoon beds, much to the delight of the Swallows and Flycatchers.
It was also a beautiful day for House People to watch their bird neighbors; for it was mild but not too bright, and every one knows how it hurts the eyes to look at flying birds with the sun shining in them.
Olive, Dodo, and Nat went out first and found Rap waiting. The Doctor followed, carrying something in his hand in a black leather case. When they arrived at the old tree in the orchard, he told them to look up. There was the perch arranged as it had been when he was a boy. Not a perch for birds, but for House People—narrow board seats fitted in between the largest branches and a bar fastened across some of the highest ones, so that it was quite safe to climb up and look out of the top of the tree. The branches had been trimmed away here and there, so that a good view could be had of what was happening elsewhere in the orchard. A scream of surprise and delight came from the group, in which Olive joined. Quickly as the children scrambled into the tree, the Doctor was up there first, laughing and saying that it was thirty years since he had climbed that apple tree; for after he went away to college the old seats had decayed and fallen down.
"Give me your hand and I'll help you up," called Nat to Rap, who had dropped his crutch and was looking up at the others.
"No, you needn't," said Rap. "I can climb all right. Sometimes it isn't so handy for me, but other times it's easier, for in tight places one leg doesn't take up as much room as two;" and he swung and pushed until he was up as high as the rest.
"Here's a nest with eggs in it," whispered Dodo, who had crept out on a limb, where a rather large round nest, made of grass and little sticks plastered together with mud, was saddled on the branch—in fact, a Robin's nest.
"Four lovely smooth eggs, not quite blue and not quite green! Please, can I have them? I saw them first."
"Think a minute, Dodo," said the Doctor. "A bird will come from each of those eggs. Suppose you take the eggs away from the poor Robins, you will be killing four young birds, besides hurting the feelings of their parents and making them leave the orchard, very likely. You must not take any eggs in the nesting season—not even one. I will tell you what happened once in a field where there were some birds' nests in the bushes.
"The man who owned the field was fond of birds and wished to protect them, but he was so good-natured that when his little boy came to him and said, 'I wish so much to have some birds' eggs—all the boys collect them—please let me take a few, father—only on our own land,' he did not wish to say 'No.' Sometimes, to be good-natured is as bad as to be cruel. This man said, 'You may take one egg from each nest, but only one, remember.' So the boy went out and took a few eggs, but then he carried them to school, showed them to the other boys, and told them where they came from. Then each boy said to himself, 'It will be all right if I take only one egg from each nest.' But when four or five boys had each taken one, all the nests were quite empty. So the poor birds left that man's field, where the bugs and worms grew and throve, till they ate up his hay and all the rest of his crops.
"When the nesting season is over eggs that have not hatched are often left in the various nests, that you can take without doing any harm. Of course I know it is not easy to keep your hands off such pretty things as birds' eggs; but if by doing so you can be patriotic and useful, it is an act of self-denial that you will be glad to do for the good of the country."
"What is in that black case, uncle?" asked Dodo. "Is it a pistol to shoot birds? I think it looks too fat for that."
"Not the kind of a pistol that you mean, Dodo, but the only kind that you youngsters need to bring down birds so that you can see them. It is a double-barrelled gun, but you must use your eyes for bullets, instead of leaden balls. See!"—and he took a fine pair of field-glasses from the case, moved the screw a little, and held them before Dodo's eyes—"what do you see down there in the grass?"
"Why, it's a Robin, but how big it looks! Every feather shows by itself, and it has white rings round its eyes like spectacles. I never saw them before, I'm sure."
Then, as the Doctor handed the glasses to Nat, Dodo looked in her lap, expecting to find the bird there instead of a hundred feet away.
"This is jolly!" cried Nat, taking a peep and passing the glasses to Rap, who put them to his eyes, gave a little "ah," and looked through them until the Doctor said, "That will do now. Olive shall keep the glasses, and whenever you children want them she will give them to you; but you must be careful never to scratch them or rub your fingers over the lenses at either end. With this magnifying instrument you will be able to see the shape of beaks and wings, and many color markings you would never notice otherwise. But what did I promise to tell you of to-day, children?"
"Citizen Bird, you said," replied Nat, "though I don't think I quite know what you mean."
"What does citizen mean?" asked the Doctor, smiling.
"I think it is a person who lives in a city, but birds aren't people and they don't live much in the city."
"You are right in one sense, my boy, but the word citizen