By far the most astonishing and marvelous feature about the bat’s anatomy is the delicate mechanism that guides it in flight. This animal has operated on the principle used by radar thousands of years before man discovered the device. The hearing is extremely acute and bats are able to receive sound impulses at a vibration frequency too high for the human ear. During flight it sends out shrill cries of high vibration frequency. As these sounds travel out through space they are reflected back by any object, large or small, that they strike. Through sensitive ears the bat receives these rebounding sounds and thus is aware at all times of the nearness of any object. This explains the bat’s uncanny ability to fly through a room in total darkness without striking even such small objects as wire or lamp cords. This ingenious device fails around water, however. Experiments have shown that a small wire stretched just above the surface of a pond is not “seen” by the bat when it swoops down to get a drink. Some bats rest in leafy treetops where they cling to small branches. Most species stay in hollow trees or caves during the daytime, and “bat caves” are common in many parts of the country, the most famous one is at Carlsbad Caverns National Park. While resting or sleeping the bat hangs head downward, always in a position to drop and fly at any moment. It is helpless on the ground, and must obtain sufficient elevation to allow for a few inches of drop before it can fly. [Illustration: One of the most elusive animals in the park is the coyote.] MOUNTAIN COYOTE _Canis latrans lestes_ Merriam The mountain coyote resembles a small collie dog in size, with a slender body, erect, pointed ears, and bushy tail. The upper parts of its body are light brownish gray, with numerous long, coarse, black hairs. The under parts are whitish, with the long hairs of the throat tipped with black. The tail is heavily tipped with black above and light beneath. The muzzle and crown of the head is a bright yellowish brown. _Specimens in park collection:_ RNP-98, Longmire Museum, Park Headquarters. The geographical distribution of the coyote includes all of western North America. The mountain coyote is found from British Columbia southward through Washington, Oregon, and the highlands of the Great Basin, Sierra Nevada and Rocky Mountains to the plateau region of northern Arizona and down the Continental Divide in New Mexico to the Mexican border. It is found locally throughout the park, at all elevations from the extreme lower portions to forest line, although usually more abundant in the vicinity of the old fire burns near the south and west boundaries.