• Webster's Revised Unabridged Dictionary
    • Patagium (Anat) In bats, an expansion of the integument uniting the fore limb with the body and extending between the elongated fingers to form the wing; in birds, the similar fold of integument uniting the fore limb with the body.
    • Patagium (Zoöl) One of a pair of small vesicular organs situated at the bases of the anterior wings of lepidopterous insects. See Illust. of Butterfly.
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Century Dictionary and Cyclopedia
    • n patagium In zoology: The extensible fold of skin of a flying mammal or reptile; the expansion of the integument of the trunk and limbs or tail, or both of these, by which bats, flying-lemurs, flying-squirrels, flying-opossums, and flying-lizards support themselves in the air. Except in the bats, the patagium does not form a wing, and the progress of the animal through the air is not a true flight, but only a greatly protracted leap. In bats the membranous expansion is stretched chiefly between the enormously lengthened digits of the hand; in the case of the other mammals named, the patagium is for the most part a fold of the common integument of the body, stretched from the fore to the hind limb. The patagia of the pterodactyls or extinct flying reptiles were wings, constructed upon lengthened digits, much like those of bats. The case is different with the flying-lizards of the present day, in which the patagium is stretched upon extended ribs. See cut at dragon. Also called parachute.
    • n patagium The fold of integument which occupies the reëntrant angle between the upper arm and the forearm of a bird, bringing the fore border of the wing to a smooth straightish free edge when the wing is closed. The tensor patagii is a muscle which puts this patagium upon the stretch.
    • n patagium In entomology, one of a pair of chitinous scales affixed to the sides of the pronotum of lepidopterous insects, just behind the head, usually covered with long scales or hairs; a shoulder-tippet. Compare tegula.
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Chambers's Twentieth Century Dictionary
    • n Patagium pat-ā-jī′um the wing-membrane of a bat, &c.: the parachute of a flying squirrel, &c.: the fold of integument between the upper arm and the forearm of a bird: one of the scales affixed to the pronotum of lepidopterous insects—the tegula.
    • ***


Webster's Revised Unabridged Dictionary
L., an edge or border
Chambers's Twentieth Century Dictionary
L., 'a gold edging.'


In literature:

As in all flying squirrels, the four legs were connected by a sheet of skin called the "patagium" which is continuous with the body.
"Camps and Trails in China" by Roy Chapman Andrews and Yvette Borup Andrews
On the misuse of the terms parapteron, hypopteron, tegula, squamula, patagium and scapula.
"Handbook of Medical Entomology" by William Albert Riley
The cartilage, moreover, which supports the patagium springs from the elbow.
"The Cambridge Natural History, Vol X., Mammalia" by Frank Evers Beddard