HETERODONTY AND PATTERNS OF TOOTH REPLACEMENT IN CROCODYLUS-NILOTICUS

Patterns of tooth replacement in the Nile crocodile Crocodylus nilotic us were evaluated in the lateral radiographs of six dried skulls of 1- year-old individuals. Additionally, the ontogeny of the succession of teeth in this species was investigated in four embryos and a hatchling , which were serially sectioned. Three-dimensional, computer-generated reconstructions of these individuals suggested that there was a regul ar pattern of odontogenic progression. Three morphogenetic zones could be identified in each of the age classes: an incisor, a canine, and a molar region. It was thus concluded that the Nile crocodile is hetero - rather than homodont. Zahnreihen, or tooth rows, with a periodicity of one were easily identified. (C) 1993 Wiley-Liss, Inc.