494 CROSS AND HOWE — RED BEDS OF SOUTHWESTERN COLORADO 



is necessary to refer to the possibility that Triassic beds occur in the 

 Canyon City region. 



Among the many remarkable fossils described by Marsh (31) from the 

 vicinity of Canyon City is a small Dinosaur, Hallopus. With his habitual 

 disregard of stratigraphic relations, Marsh gave neither precise locality 

 nor horizon for this fossil, treating it as belonging with the Atlantosau- 

 rus fauna, but it has recently been announced by Williston (45) that 

 Hallopus is, in his opinion, of Triassic affinities, while the Atlantosaurus 

 fauna is considered Lower Cretaceous. It is certain that no considerable 

 thickness of Triassic beds can exist between the Morrison and Fountain 

 formations in the Canyon City-Garden Park district, but a thin Triassic 

 remnant may well be present, locally at least. The relation of the Hal- 

 lopus horizon to the Belodon bed of the Purgatoire canyon is of course 

 wholly unknown. 



Triassic beds of northern Neiv Mexico. — While Marcou and other early 

 explorers of New Mexico announced the presence there of Triassic for- 

 mations, the first fossils indicating the correctness of this assertion were 

 obtained by Newberry in 1859. The fossils described by Newberry 

 himself were fossil plants obtained from the old copper mines near 

 Abiquiu, a locality on Chama river some 20 miles or less above its junc- 

 tion with the Rio Grande (33, pages 67-69). The plants are mainly 

 cycads and conifers, and as they have not been identified at many other 

 localities they are of less importance to the present discussion than the 

 vertebrate remains described by Cope, to which reference will soon be 

 made. 



The formation from which the Abiquiu plants were obtained is de- 

 scribed by Newberry as consisting mainly of red sandstones, with con- 

 glomerates and many variegated beds of soft shales, with abundant saline 

 efflorescences, which led him to characterize the Red beds of New Mexico 

 and Arizona in general as the ''Saliferous series." Fossil wood, often in 

 tree trunks, is mentioned. 



Although I can not find that Newberry mentions vertebrate fossils in 

 the Triassic beds of Chama valley, it appears that he found some, for Cope, 

 who followed him in the exploration of the region, states that the first 

 invertebrates from the Trias of the Rocky mountains were collected by 

 Newberry with the Macomb expedition. Cope visited Chama valley and 

 the Gallinas mountains, lying to the west of it, in 1864, while on the 

 Wheeler Survey, and obtained various vertebrate fossils from the Triassic 

 beds (1). 



The fragmentary remains described by Cope embrace teeth and bones 

 of 3 dinosaurs, 2 of which were generically determined as Laelaps and 

 Palseoctonus. Similar portions of a belodont crocodile were called Typo- 

 thorax coccinarium. Associated with these were found 5 species of Unio- 



