New three-color photometi y is reported for fifty-six stars previously known to be subdwarfs but for which photometric data were meager or lacking. Photometry is also reported for an additional ninety- four stars observed as candidates in a pilot program to discover new subdwarfs. Forty-four of the candidate stars were found to have ultraviolet excess values exceeding 0"'.l0, and of these, twenty-seven have - B) > 0"'16 which puts them in the class of extreme subdwarfs similar to stars on the main sequences of the halo globular clusters. Radial velocities have been obtained and are reported for many of the new extreme subdwarfs. The distribution of the B - V colors for subdwarfs wfth (U - B) > 0" 16 shows an abrupt blue cutoff at B - V = 0"'.38 if no reddening corrections are applied, or B - V = 0"'.34 if the Parenago reddening equation is used. Both values are bluer by 0"'.04 and 0w08 than the previously reported colors of the main-sequence termination points of the well-studied halo clusters. This tends to support the belief that the true termination colors for the main sequences of halo globular clusters are bluer than previously suspected, due either to interstellar reddening (Arp 1962b), or to small errors in previous faint photometry, or to both. If this is confirmed by direct observations in the halo clusters themselves, then ages of these clusters would be closer to 1010 years than to 2 X 1010 years.