The Palatal Structure of some Canadian Hadrosauridae (Reptilia: Ornithischia): Discussion

Abstract

phus osborni may be from the Cretaceous at Edmonton; nothing else can he deduced concerning the ages or localities for these four spccies and nothing at all for the other five species discussed. The abstract includes the statement Two distinct hadrosaurian lineages can be delineated, each showing changes from possible hypsiIophodont ancestors. Knowledge of the age of the taxa is critical to evaluation of whether these could be true lineages or just msrphological series, without possibilities of ancestordescendant relations. Stratigraphic and gcographic data are very important in paleontology and the inclusion of this material would have improved the contribution of Heaton's paper. Such data would have expanded the paper by a few lines. The responsibility for ensuring that an author has included such necessary data is a natural function of a the text is any further geographic data pre- critical reade; experienced in the general field sented. Detective work on Heaton's references of a manuscript. I reveals that Coryrho,saurus casuarius is from the Cretaceous that Ednzonto- HE* ro~, M. J. 1972. The palatal structure of some Canasauru,s regalis may be from the Edmonton For- dian Hadrosauridae (Werrtilia: QrnithischiaB. Can. J. mation, that ~rit~murus notabilis may be from Earth Sci. 9, pp. 185-205% thc Belly River Formation, and that Saurolo