The Sixth Principal Meridian extends from the base line coincident with the north boundary of Kansas

Kansas

Kansas is a US state located in the Midwestern United States. It is named after the Kansas River which flows through it, which in turn was named after the Kansa Native American tribe, which inhabited the area. The tribe's name is often said to mean "people of the wind" or "people of the south...

 in latitude 40°N

40th parallel north

The 40th parallel north is a circle of latitude that is 40 degrees north of the Earth's equatorial plane. It crosses Europe, the Mediterranean Sea, Asia, the Pacific Ocean, North America, and the Atlantic Ocean....

 south through the state to its south boundary in latitude 37°N

37th parallel north

The 37th parallel north is a circle of latitude that is 37 degrees north of the Earth's equatorial plane. It crosses Europe, the Mediterranean Sea, Africa, Asia, the Pacific Ocean, North America, and the Atlantic Ocean....

 and north through Nebraska

Nebraska

Nebraska is a state on the Great Plains of the Midwestern United States. The state's capital is Lincoln and its largest city is Omaha, on the Missouri River....

 to the Missouri River

Missouri River

The Missouri River flows through the central United States, and is a tributary of the Mississippi River. It is the longest river in North America and drains the third largest area, though only the thirteenth largest by discharge. The Missouri's watershed encompasses most of the American Great...

 and governs the surveys in Kansas and Nebraska; the surveys in Wyoming

Wyoming

Wyoming is a state in the mountain region of the Western United States. The western two thirds of the state is covered mostly with the mountain ranges and rangelands in the foothills of the Eastern Rocky Mountains, while the eastern third of the state is high elevation prairie known as the High...

 except those referred to the Wind River Meridian

Wind River Meridian

The Wind River Meridian, established in 1875, is one of the principal meridians for Wyoming. The initial point is near Fort Washakie, Wyoming....

 and base line, which intersect in latitude 43°01'20"N and longitude 108°48'40"W from Greenwich; the surveys in Colorado

Colorado

Colorado is a U.S. state that encompasses much of the Rocky Mountains as well as the northeastern portion of the Colorado Plateau and the western edge of the Great Plains...

 except those projected from the New Mexico

New Mexico Meridian

The New Mexico Meridian, is longitude 106° 53' 40" west from Greenwich. It extends throughout New Mexico and into Colorado, and together with the baseline, at latitude 34° 15' 25" north, governs township and range surveys in New Mexico, except those in the northwest corner of the state which refer...

 and Ute Meridian

Ute Meridian

The Ute Meridian, also known as the Grand River Meridian, was established in 1880 and is a principal meridian of Colorado....

s the latter intersecting its base line in latitude 39°06'40"N and longitude 108°33'20"W from Greenwich; and the surveys in South Dakota

South Dakota

South Dakota is a state located in the Midwestern region of the United States. It is named after the Lakota and Dakota Sioux American Indian tribes. Once a part of Dakota Territory, South Dakota became a state on November 2, 1889. The state has an area of and an estimated population of just over...

 extended or to be extended over the tract embracing the Pine Ridge

Pine Ridge Indian Reservation

The Pine Ridge Indian Reservation is an Oglala Sioux Native American reservation located in the U.S. state of South Dakota. Originally included within the territory of the Great Sioux Reservation, Pine Ridge was established in 1889 in the southwest corner of South Dakota on the Nebraska border...

 and Rosebud Indian Reservation

Rosebud Indian Reservation

The Rosebud Indian Reservation is an Indian reservation in South Dakota, United States. It is the home of the federally recognized Sicangu Oyate, also known as Sicangu Lakota, the Upper Brulé Sioux Nation, and the Rosebud Sioux Tribe , a branch of the Lakota people...

s.