National Geographic : 1932 Jul
SEEKING THE SMALLEST FEATHERED CREATURES Photograph by Wright M. Pierce THE NEST OF A BLACK-CHINNED HUMMING BIRD Near Claremont, California, the hummer built a nest made exclusively of yellowish down from the back of sycamore leaves (see text, page 74). Most hummers have straight bills, but there is the sicklebill, in which the bill is curved so that its outline forms one-third of a circle. Such adaptations allow feed ing in special flowers, the sword-bearer frequenting long, trumpet-shaped blos soms, while the sicklebill is partial to cer tain orchids, palms, and other peculiar blossoms, where the throat of the flower is curved. Variations in the form of the tail in this group are equally remarkable. Most spe cies have the feathers of ordinary length, forming a square or slightly notched tail, but in contrast to these there are the racket tailed hummers (Spathura), in which the lateral feathers are greatly elongated, with the tip narrowed and then expanded so that it resembles a racket. The long-tailed hummers have tails three or four times as long as the body, the longest feathers being seven inches in length. It is usual for male humming birds to have a spot of brilliant iridescent color on the throat. With this there are often pe culiar feather developments in the form of crests, or gorgets, that provide increased surface for these areas of brilliant color, and often produce most remarkable and extraordinary appearances. I recall my pleasure and surprise at my first glimpse of the gilt-crested humming bird on the wing. In search of specimens for the National Museum, I had come to the little island of Vieques, east of Puerto Rico, in the West Indies, and on my first morning in the country collected a tiny hummer feeding at flowers in the top of a small tree. In the air it had appeared ordi nary, but, to my amazement, when it came to my hand it possessed a long, pointed crest of the most brilliant green imaginable. CUP-SHAPED NESTS OF SOFT DOWN The nests of humming birds are made of soft plant downs, formed into a cup-shaped structure that in most instances is placed firmly on some small twig or branch, some times near the ground and sometimes high above it. The outside of this structure usually is covered with bits of bark and moss bound in place with spider web, so that the nest is inconspicuous, resembling merely a knot on a limb. Some species attach their nests to leaves or to the ends of branches, so that they are semipendent.