1914] Buwalda: Tertiary Mammal Beds in West-Central Nevada 337 



The Cedar Mountain area here discussed comprises parts of two 

 relatively broad valleys, trending roughly north and south, and parts 

 of certain rather prominent mountain ranges separating the valleys 

 (pi. 33). The most easterly of the two valleys is the southward con- 

 tinuation of lone Valley proper, and will be considered as part of it ; 

 the westerly one is the southward extension of Stewart Valley, and 

 will be referred to as part of that valley. To the east of lone Valley 

 are the Shoshone Mountains, rising to a maximum height of about 

 0500 feet ; between lone and Stewart valleys lie the northern end of 

 Cedar Mountain and the southern end of the Paradise Range. A 

 depression between the ends of the two ranges in a sense connects 

 lone and Stewart valleys. Cedar Mountain rises to about 8000 feet 

 in Little Pilot Peak ; the Paradise Range attains an elevation of about 

 8700 feet. The west side of Stewart Valley is bounded by the south- 

 eastern end of the Gabbs Valley Range, in which the peaks also rise 

 to something over 8000 feet. Practically the entire area of the gently 

 sloping valley surfaces of both lone and Stewart valleys lies between 

 the 5500 and 6500-foot contours. In common with the whole of the 

 Great Basin, this region has an arid climate, and consequently scanty 

 vegetation. 



While Stewart and lone valleys are broad, they are not flat-floored 

 like stream valleys. Their surfaces are in large part quite even, but 

 they slope gently downward from the range flanks toward the main 

 wash which runs along the middle of each valley. The washes drain 

 into playa lakes. The valley slopes sometimes merge almost insensibly 

 into the mountain sides ; at other localities the gentle valley slopes 

 and the steeper mountain sides meet abruptly. At such places the 

 line between gentle and steep slopes indicates roughly the contact 

 between the softer lacustral strata and the more resistant formations. 

 Considerable parts of the valley areas have been cut up by gulches, 

 which have developed a badland topography. In some places masses 

 of the older underlying rocks protrude above the even surface of the 

 softer beds in the valleys. The ranges, being made up of older and 

 more resistant terranes, have slopes which are usually considerably 

 steeper than those developed on the softer rocks in the valleys. The 

 range slopes are usually on bare rock, or are but thinly covered by the 

 products of rock disintegration. 



