BAT  ,1 a name for any member of the zoological

order Chiroptera (q.v.) . Bats are insectivorous animals modified for flight, i M . E. bakke, the change to " bat " having apparently been influenced by Lat. batta, blatta, moth . The word is thus distinct from the other common term " bat," the implement for striking, which is probably connected with Fr. battre, though a Celtic or simply onomatopoetic origin has been suggested.with slight powers of progression on the ground; the patagium or "flying-membrane" of some squirrels and of Galeopithecus (q.v.) probably indicates the way in which the modification. was effected . • They are distributed throughout the world, but are most abundant in the tropics and the warmer parts of the temperate zones; within these limits the largest forms occur . There is great variation in size; the Malay "flying-fox " (Pteropus edulis) measures about a foot in the head and body, and has a wing-spread of 5 ft.; while in the smaller forms the head and body may be only about 2 in., and the wing-spread no more than a foot . The coloration is generally sombre, but to this there are exceptions; the fruit-bats are brownish yellow or russet on the under surface; two South American species are white; Blainville's chin-leafed bat is bright orange; and the Indian painted bat (Cerivoula pieta) with its deep orange dress, spotted with black on the wing-membranes, has reminded observers of a large butterfly . In habits bats are social, non, turnal and crepuscular; the insect-eating species feed on the wing, in winter in the temperate regions they migrate to a warmer climate, or hibernate, as do the British bats . The sense-organs are highly developed; the wing-membranes are exceedingly sensitive; the nose-leaf is also an organ of perception, and the external ear is specially modified to receive sound= waves . Most bats are insect-eaters, but the tropical " flying foxes " or fox-bats of the Old World live on fruit; some are blood-suckers, and two feed on small fish . Twelve species are British, among which are the pipistrelle (Pipistrellus pygmaeus, or P. pipistrellus), the long-eared bat (Plecotus auritus), the noctule (Pipistrellus [Pterygistesl noctulus) the greater and lesser horseshoe bats (Rhinolophus ferrum-equinum and R. hipposiderus), &c .