A BIRD'S BIOGRAPHY. 73 tlian in central Illinois or at Washington, D. C, and a week earlier than at Boston. In the fall these conditions are reversed. A BlnVs Biography. — As a further guide to your observation a list of the principal details which enter into a bird's hf e-historj is appended : 1. Description (of size, form, color, and markings). 2. Haunts (upland, lowland, lakes, rivers, woods, fields, etc.). 3. Movements (slow or active, hops, walks, creeps, swims, tail wagged, etc.). 4. Appearance (alert, pensive, crest erect, tail drooped, etc.). 5. Disposition (social, solitary, wary, unsuspicious, etc.). 6. Flight (slow, rapid, direct, undulating, . soaring, sailing, flapping, etc.). 7. Song (pleasing, unattractive, continuous, short, loud, low, sung from the ground, from a perch, in the air, etc. ; season of song). 8. Call-notes (of surprise, alarm, protest, warning, signaling, etc.). 9. Season (spring, fall, summer, winter, with times of ar- rival and departure, and variations in num- bers). 10. Food (berries, insects, seeds, etc. ; how secured). 11. Mating (habits during courtship). 12. Nesting (choice of site, material, construction, eggs, incu- bation). 13. The Young (food and care of, time in the nest, notes, actions flight). From observations of this kind, consisting of a simple statement of facts, you may philosophize according to your nature on the relation between habit and structure, colors and haunts, and intelligent adaptation to new con- ditions. Beware, however, lest you be led to draw faulty conclusions from insufficient observation. Do not make the individual stand for its species, or the species for its family, and remember that one is warranted in theorizing only when the facts in the case are facts indeed. 12
