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Bat Hair

Bat Hair

This hair is from the McCrone Hair Standard set. this shows the coronal scale pattern and the pigment distribution in the last third of the hair from the root end. The medulla is indistinct.

Transmitted 20 Degrees Off Crossed Linear Polarized Light


This hair belongs to the Order Chiroptera, Bats. This is a very large Order with about 1,100 speces.

Significance in the Environment:

The presence of these hairs in an indoor sample indicates a possible attic infestation.

Characteristic Features:

Bat hair is around 10 micrometers wide from the root to near the tip. It has an indistinct medulla (none visible). The cuticle pattern is simple coronal. The scale count is about 8 per 100 micrometers. Bat hair has a refractive index along its length of about 1.56 and perpendicular to its length of about 1.55. It has a birefringence of about 0.01 and a positive sign of elongation.

Associated Particles:


References with Photographs and/or Drawings

Hausman, Leon Augustus, "Structural charactreistics of the hair of mammals", THE AMERICAN NATURALIST, vol. 54, no. 635, pp.496-523,

Hausman, Leon Augustus, "Recent studies of hair structure relationships", THE SCIENTIFIC MONTHLY, pp. 258-277,

Glaister, John, A STUDY OF HAIRS AND WOOLS, Misr Press, Cairo, 1931.

FBI site for Animal Hair Identification:

Keys Only

Mayer, William V., "The hair of California mammals with keys to the dorsal guard hairs of California mammals", THE AMERICAN MIDLAND NATURALIST, vol. 48, no. 2, pp. 480-512, 1952.

Stains, Howard J., "Field key to guard hair of middle western furbearers", JOURNAL OF WILDLIFE MANAGEMENT, vol. 22, no.1, pp. 95-97, January, 1958.

Mathiak, Harold A., "A key to hairs of the mammals of southern Michigan", JOURNAL OF WILDLIFE MANAGEMENT, vol. 2, no. 4, pp. 251-268, October, 1938.