1. Extend the foregoing methods of study to the following passerine birds:—Starling, finches, wagtails, pipits, nuthatch, tits, warblers, wrens, and flycatchers, and make notes of the observations. 2. Try to discover reasons for grouping (a) woodpeckers, nightjars, and kingfishers with swifts and cuckoos; (b) pheasants and grouse with fowls. 3. Compare geese and swans with ducks, and make notes of as many points of resemblance and difference as possible. 4. Compare and contrast owls with hawks. 5. Arrange the above birds in lists according to (a) food, and the characters of the beak; (b) characters of feet and arrangement of toes; (c) nests (open-topped, covered, built in holes or tunnels); (d) colour and number of eggs; (e) condition of young at time of hatching. 6. How many birds do you know which (a) spend only the summer, (b) spend only the winter, (c) stay all the year, in this country? State, in each instance, upon what food the bird most depends. [Pg 332] CHAPTER XVIII. FROGS AND TADPOLES. 60. THE LIFE OF THE FROG. 1. Manner of life.—Where have you found frogs? Are they commonest in dry or in damp situations? At what time of the year have you seen them actually in water? How do frogs move about? Do they walk or hop? Chase a frog, and notice that its hops become shorter as it is pursued. Upon what does the frog feed? Have you ever seen frogs abroad in the depth of winter? Are insects common in winter? How do you suppose frogs spend the winter? What are the principal enemies of frogs?