The record of carbon-13 (delta13 C) variations in DH-11 vein calcite core from Devils Hole, Nevada, shows four prominent minima near glacial terminations (glacial-interglacial transitions) V to II. The delta13 C time series is inversely correlated with the DH-11 oxygen isotope ratio time series and leads it by as much as 7000 years. The delta13 C variations likely record fluctuations in the delta13 C of dissolved inorganic carbon of water recharging the aquifer. How such variations are transported 80 kilometers to Devils Hole without obliteration by waterrock reaction remains an enigma. The record may reflect (i) global variations in the delta13 C of atmospheric CO2 and, hence, the delta13 C of continental biomass or (ii) variations in extent and density of vegetation in the southern Great Basin. In the latter case, delta13 C minima at 414, 334, 246, and 133 thousand years ago mark times of maximum vegetation.