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 70 YOUNG BIRDS. Among some species both sexes share equally the task of incubation. In others, the female is longer on the nest, the male taking her place during a short period each day while she is feeding. Less frequently the female is not at all assisted by her mate, and in some cases — Os- triches, Emus, Phalaropes, and a few others — the male alone incubates. The Young. — The care of the young and their men- tal and physical development afford us unequaled oppor- tunities for the study of bird character. We may now become acquainted not only with the species but with individual birds, and at a time when the greatest demands are made upon their intelligence. We may see the seed-eaters gathering insects and per- haps beating them into a pulp before giving them to their nestlings : or we may learn how the Doves, High-holes, and Hummingbirds pump softened food from their crops down the throats of their offspring. The activity of the parents at this season is amazing. Think of the day's work before a pair of Chickadees vidth a family of six or eight fledglings clamoring for food from daylight to dark ! But the young birds themselves furnish far more in- teresting and valuable subjects for study. None of the higher animals can be reared so easily vdthout the aid of a parent. AVe therefore can not only study their growth of body and mind when in the nest and attended by their parents, but we can isolate the young of prsecocial birds, such as Chickens, from other birds and study their mental development where they have no opportunity to learn by imitation. In this way students of instinct and heredity have obtained most valuable results.* York city).
 * Read Lloyd Morgan's Habit and Instinct (Edward Arnold, New