EARLY REPTILIAN EVOLUTION RE-VIEWED.

摘要: Most reptiles, living and fossil, can be arrayed in a small series of subclasses or superorders, clearly distinguishable from one another, all, presumably, derived the ancient "stem reptiles," Cotylosauria. A customary type classification, based originally on nature temporal openings, was first fully developed by Williston (1925). It is now obvious that other features than "key characters" structure must taken into account, but, with necessary modifications, I have followed this system successive editions my "Vertebrate Paleontology" (1933, 1945, 1966) "Osteology Reptiles" (1956). Apart few debatable points (such as whether all two-arched reptiles should included single subclass Diapsida divided Archosauria Lepidosauria), most recent writers similar "orthodox" pattern reptilian classification phylogeny. Two divergent systems, however, deserve serious consideration, since they been proposed major workers fossil reptiles: Prof. D. M. S. Watson University College, London, F. von Huene Tiibingen.