and just northeast of the Amargosa River. Several springs overflow into pools totaling 6.6 acres (2.7 ha) in area, making the site the third largest marsh in the park. The pools provide habitat for several endemic species, including the Saratoga Springs pupfish. Other rare species present include the Amargosa tryonia snail, the Amargosa springsnail, the Saratoga Springs belostoma bug, the Amargosa naucorid bug, and the Death Valley June beetle. Plant life includes common reeds, bulrush and saltgrass. The springs were probably named in 1871 by the Wheeler Survey after the resort town of Saratoga Springs, New York, and were an important water source for the twenty-mule teams of the 1880s. The area saw a failed nitrate rush in 1902, and similarly unsuccessful attempts to mine gold and silver in the middle part of the decade. The Pacific Nitrate Company arrived in 1909 and built a small camp, but left within a few years. From the 1930s through the 1960s the springs provided water for the successful talc mines in the nearby Ibex Hills. Except for two partially collapsed stone structures, little evidence remains of human habitation at the spring. A dirt road provides access to an overlook of the area, but human entry into the wetland itself is prohibited in order to the protect the sensitive habitat. Scotty's Castle Shoreline Butte This desert butte was once an island in a lake that filled Death Valley several times during the Pleistocene ice ages. Scientists call all manifestations of this large body of water Lake Manly. There are different horizontal linear features on the northeast flank of the butte that are ancient shorelines from this lake. It takes some time for waves to gnaw away terraces like the ones seen on Shoreline Butte, so these benches provide records of times when the lake level stabilized long enough for waves to leave their mark on the rock. The highest strandline is one of the principal clues that geologists use to estimate the depth of the lake that once filled Death Valley. Shorelines of ancient Lake Manly are preserved in several parts of Death Valley, but nowhere is the record as clear as at Shoreline Butte. Several lakes have occupied Death Valley since the close of the Pleistocene epoch 10,000 years ago, but these younger lakes were quite shallow compared to Lake Manly (See Badwater and Devils Golf Course above). Teakettle Junction At the