TRIASSIC. 429 



of the West to the same horizon ; and as they were in beds of continuous sedi- 

 mentation, or apparently so, and were conformable in deposition, it was hard 

 to give the dividing line between any of the beds. 



The fact is, no doubt, that the Red Beds of the west when properly under- 

 stood will be found to consist of beds belonging to all the subdivisions from 

 the Coal Measures to the Cretaceous. In Texas the beds are very easily iden- 

 tified on stratigraphical and paleontological grounds. The Permian is very 

 easily distinguished from the Carboniferous below, as between the contact of 

 the beds there is a great hiatus in time, and when the whole contact is under 

 consideration, is very different in sedimentation or stratigraphy. The Per- 

 mian is well represented by both vertebrate and invertebrate fossils. The 

 Triassic has also an abundant and characteristic fauna and flora, and between 

 the Permian and Triassic in Texas there must have elapsed a considerable 

 period. The upper part of the Permian was deposited in a shallow sea, 

 where waters were highly charged with sulphate of lime and chloride of so- 

 dium ; while the Triassic beds were deposited in a shallow fresh water sea, where 

 a great deal of fresh water poured in from the mountains, containing a great 

 many pebbles and much timber. The Permian has a continuous sedimenta- 

 tion of sandy clays, sandstones, and gypsum with no conglomerates, and with 

 a regular dip to the northwest at a small angle; while the Triassic is entirely 

 free from salts of any kind, and in the bottom part is largely composed of 

 conglomerates and fragments of petrified wood, and dips towards the south- 

 east at as small an angle, or in the opposite direction from that of the Per- 

 mian. So there is no trouble in determining the line between the Permian 

 and Triassic. 



Only the upper part of the Permian is found north and west of the Wich- 

 ita Mountains and along the Canadian River, and in that there are fewer fossils 

 than elsewhere in the Permian strata, so that any one visiting that part of the 

 formation might not find fossils sufficient to determine the horizon definitely 

 or satisfactorily, and the mistake might very easily be made of calling all of 

 the beds Triassic ; while to the south and south westward of the Wichita range 

 no such mistake need to be made, because the fossils are numerous and dis- 

 tinctive. 



Sufficient data has not been obtained to determine the exact horizon to 

 which the Triassic beds on the eastern side of the Staked Plains should be 

 referred in the series, but I do not think they will be found to be the lowest 

 part of that division in the northwest. It is very evident, however, that 

 there was not a continuous sedimentation between the Permian and Triassic. 



