40 MESOZOIC FLORAS OF UNITED STATES. 



It has a length of 44 miles and embraces all the phases of each of the sub- 

 divisions of the system. It is therefore the principal section of the 

 lower Little Colorado Valley. 



Description of the section shovm, in fig. 3. 



1. Carboniferous limestone (thickness unknown). -peet 



2. Moencopie formation _ 5qq 



3. Lithodendron member gOQ 



4. Variegated marls _ 400 



5. Sandstone ledge _ j^qq 



6. Limestones and mortar beds 200 



7. Variegated sandstones _ ggo 



8. Brown sandstones _ _ . 3qq 



9. WHte sandstones jqq 



Total thickness •_ 3 qoO 



SECTION IV.—WIN8L0W. 

 [PI. IV, G-H.] 



This section begins with the canyon of Clear Creek, which is formed 

 by heaAy Carboniferous sandstone beds. It passes through the town of 

 Winslow and crosses the Little Colorado just above old Brigham City, 

 goes through Sunset, and follows nearly the line of the old trail from 

 Sunset to Keams Canyon, passing near Pottery Hill, Chimney Butte, 

 Castle Butte, the Moqui Buttes, Comar Spring, and Jettyto Spring. It 

 therefore embraces considerable of the overlying Cretaceous and other 

 later formations, the Trias extending some distance north of the southern 

 boundary line of the Navajo Reservation. 



Description of the section shown in fig. 4. 



1. Carboniferous sandstone (thickness unknown). p^^j 



2. Moencopie formation gQQ 



3. Lithodendron member 7qO 



4. A'ariegated marls 4qq 



5. Limestones and mortar beds 300 



6. Variegated sandstones gQQ 



7. Brown and white sandstones. 3OO 



3,000 



8. Cretaceous lignite bed 50 



9. Cretaceous 750 



Total thickness 3 goo 



No. 8 is variable and No. 9 is estimated. 



