"That is why I have so often found dead birds along the turnpike under the telegraph wires," said Rap. "Yes, Rap, the inventions of man are very wonderful, but some of them have been sad things for Bird People, and this is another reason why we should protect them whenever we can. These journeys that the birds make when they leave their nesting haunts for the winter season, and return again in spring, are called _migrations_. The word 'migrate' means to move from one country to another with the intention of remaining there for some time. The birds who only make little trips about the country, never staying long in one place, we call visitors. "Birds may be divided according to their journeys into three groups, which will help you to place them: "1. Citizens. "Those Bird People whose families stay in or near the same place the year round, roving about somewhat according to the food-supply and weather. "2. Summer Citizens. "The families that, though they are with us but six or eight months of the year, make their homes here, and pay their rent and taxes by working for the common good. As they are almost all insect-eaters, they are even more useful than the stay-at-home Citizens, who are chiefly seed-eaters or cannibals. "3. Winter Visitors. "The birds who come down from the North in severe weather, but do not stay in one place for any particular time, arriving one day and disappearing the next. They glean for their scanty board and return to the cold countries, of which they are Citizens, before nesting-time." "Please tell me the names of some of the birds that live here all the time," said Nat. "Have I seen any yet?" "I think the Bluebird, the Robin, and the Song Sparrow are Citizens," said Rap, "because last winter I used to see one of two almost every day, unless the snow and ice were very thick." "Yes," said the Doctor, "the Bluebird is a Citizen in the Middle and Southern States, and the Robin also. But in the more northerly parts they are Summer Citizens, returning early and staying late. But the Song Sparrow is a Citizen almost everywhere, and is known about every bushy garden from the east coast to the west, and from the cotton plantation to the land of snow." "Please tell me the names of some winter visitors," said Rap. "Isn't the Great White Owl one of these?" "Yes, the Snowy Owl is one of them; so is the Snowflake, who comes to us on the wings of the storm; the tiny Winter Wren, the Great Northern Shrike, and many others, who arrive when snow-tide is upon us in the temperate part of the country, after our song birds have flown to the warmer south. You shall hear of all these, and learn where each one lives, in the bird stories I am going to write for you. But now let us go down by the river and see what some of these newly arrived birds are doing after their long journey.