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We present abundance analyses based on high dispersion and highsignal-to-noise ratio Magellan spectra of two highly microlensed Galactic bulgestars in the region of the main sequence turnoff with Teff ~ 5650 K. We findthat MOA-2008-BLG310 has [Fe/H]= +0.41 (+,- 0.09 dex) and MOA-2008-BLG311 has+0.26 (+, - 0.09 dex). The abundance ratios for the ~20 elements for whichfeatures could be detected in the spectra of each of the two stars follow thetrends with [Fe/H] found among samples of bulge giants. Combining these twobulge dwarfs with the results from previous abundance analysis of four otherGalactic bulge turnoff region stars, all highly magnified by microlensing,gives a mean [Fe/H] of +0.29dex. This implies that there there is aninconsistency between the Fe-metallicity distribution of the microlensed bulgedwarfs and that derived by the many previous estimates based on surveys ofcool, luminous bulge giants, which have mean [Fe/H] ~ -0.1 dex. A number ofpossible mechanisms for producing this difference are discussed. If oneascribes this inconsistency to systematic errors in the abundance analyses, weprovide statistical arguments suggesting that a substantial systematic error inthe Fe-metallicity for one or both of the two cases, bulge dwarfs vs bulgegiants, is required which is probably larger than can realistically beaccommodated.

Clues to the Metallicity Distribution in the Galactic Bulge: Abundances in MOA-2008-BLG310 and MOA-2008-BLG311