[Illustration: THE LYRE-TAILED NIGHT JAR (_Hydropsalis forcipata_).]
The LYRE-TAILED NIGHT JAR (_Hydropsalis forcipata_), as the species with
which we are most familiar has been called, is spotted with brown and
yellow upon its body, the centre of the throat being white. The exterior
tail-feathers of this beautiful bird are from twenty-six to twenty-eight
inches long, while the body does not exceed seven, and the wing nine
inches. According to Azara, the Lyre-tailed Night Jar is somewhat rarely
met with, as it usually frequents the inmost recesses of the vast forests
of South America. Its scientific name, _Hydropsalis_, has been derived
from the fact that like other Night Swallows it flies close to the water
when passing over the lakes or rivers in search of food.
Some Goatsuckers have certain feathers of their wings so remarkably
developed, that they have been called by the Arabs "_the four-winged
birds_," and are described by Swainson under the name of MACRODIPTERYX.