MORPHOLOGY OF HORNS IN WOOLLY RHINOCEROS, COELODONTA-ANTIQUITATIS

Macro-and microstructure of nasal and frontal hems in Coelodonta antiq uitatis found in the Yana-Kolyma Lowland in 1988-89 are described. The nasal horn is the largest one among the known specimens, the length o f its anterior curvature is 130-135 cm. The horn is flattened along th e whole length, has a pronounced transverse banding and deeply worn ve ntral surface. The frontal horn is of relatively small size, differs i n shape from all the known frontal hems. Both horns demonstrate micros tructure, characteristic of this kind of dermal derivatives. They cons ist of hollow tubes (''filaments'') oriented along the horn long axis and placed in cells of the corneous base (''matrix''). Architectonics of woolly rhinoceros hems is compared with that in hairs of the same s pecies, with hems and hairs of recent Diceros bicornis, with architect onics of horse hoof and gray whale (Eschrichtius gibbosus) baleen. Som e details of filament morphology, and their association with other ele ments of architectonics are supposed to be related to specific feature s of horn growth and functioning.