Transmitted Oblique Brightfield Illumination
                
Definition/Function:
                Mammalian hair is composed of a protein, keratin. It is the same protein that makes
                  horn, fingernails, claws, skin epithelium, and dander.
                  Mammalian hair consists of three distinct morphological units, the cuticle, the
                  cortex and the medulla. The distinctive pattern shown by these
                  units varies over the length of the hair in a way that can be very characteristic.
                  The patterns exhibited by these units
                  in any given hair are often sufficient to identify the genus, the species, or even
                  the individual that the hair came from.
                Significance in the Environment:
                Characteristic Features:
                Associated Particles:
                References:
                References with Photographs and/or Drawings
                von Bergen, Werner (ed.), WOOL HANDBOOK, Interscience Publisher, pp. 437-445,
                1963.
                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:
                http://www.fbi.gov/hq/lab/fsc/backissu/july2004/research/2004_03_research02.htm
                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.