[lambe] progress of VERTEBRATE PALEONTOLOGY 21 



8. Fauna of the Cretaceous. Niobraea-Benton (Colorado 

 formation). — The fish remains, from the Niobrara-Benton of the Cre- 

 taceous of Manitoba, represent in all four species of different genera. 

 Lamna manitohensis, a Selachian of the suborder Asiterospondyli, is 

 known only from detached teeth. The second species, Ptycliodus 

 parvulus, also a Selachian, but of the suborder Tectospondyli, and be- 

 longing to the family of Myliobatidaî (eagle rays), is founded on a 

 single tooth. The two remaining species are Teleostomes, one 

 Enchodus shumardi, described by Leidy from the Cretaceous of Neb- 

 raska, is represented by portions of the jaws with teeth, the other 

 Cladocyclus occidentalis, Leidy, also a Nebraskan Cretaceous species, is 

 recorded on the evidence of detached cycloid scales. E. shumardi 

 and C. occidentalis are both Actinopterygians, the former of the sub- 

 order Isospondyli, the latter belonging to the Percesoees. 



9. Fauna of the Cretaceous. Belly Eiver series. — The next 

 fauna to be considered, that of the Belly Eiver series, includes fishes, 

 a batrachian, reptiles and mammals, and has a greater diversity of 

 forms and a larger number of species than any of the preceding ones. 



This fauna is decidedly archaic in some of its features and progres- 

 sive in others, forming a connecting link between the known faunas 

 of the upper Jurassic and the uppermost Cretaceous, and helps to reduce 

 the gap in the geological records of the land inhabitants of early Cre- 

 taceous times. 



Most of the fossils included in this fauna were obtained by the 

 writer in 1897, 1898 and 1901 in the Eed Deer river district in Alberta, 

 and are described in part II of volume III (quarto) of Contributions to 

 Canadian Palseontolog}'. 



Among the fishes we have representatives of Elasmobranchs, 

 Ganoids and Teleosits. We are able to record the occurrence of only 

 one Amphibian, a Urodele species of the Batrachia. The synapsidan 

 reptiles include plesiosaurs, and turtles of the three suborders 

 Pleurodira, Cryptodira and Trionychia. Those of the Diapsida are, 

 a species of the order Choristodera, Dinosauria of the two suborders 

 Theropoda and Orthopoda, Squamata, Lacertilia and Crocodilia. Two 

 mammals are an interesting feature of the fauna. 



The Selachian Myledaphus hipartitus, placed with the Myliobatidaî 

 is known only from separate teeth. Cope's description was based on 

 teeth from Montana, the genus being doubtfully referred to the Eays. 

 Of the "ganoid" Actinopterygii there are two species, one, Acipenser 

 alhertensis belonging to the Chondrostei, and founded on a keeled and 

 ornamented shield, the other, Lepidosteus occidentalis, of the suborder 

 Aëtheospondyli was described originally by Leidy from separate scales. 



