Dentition of Ornithorhynchus

Abstract

IN 1888 Poulton, when examining some sections of the head of a young platypus, made the very important discovery of true calcified teeth. In the upper jaw he found evidence of four teeth, and he believed that four would also be found in the mandible. He also says: ” I think that it is probable that the rudiments of teeth may be found anterior at a much earlier stage”.