Note that this list is not authoritative and it is present here mainly so climbers can log their ascents. If you are serious about county highpointing in Texas, then you should visit the County Highpointing Web Site, join the Yahoo County Highpointing Group, and refer to Andy Martin's book for the definitive listing of all the points.
Texas has more counties than any other state, and large sections of the state have very low relief. Additionally, many of these high points are on private land and require landowner permission. To date (early 2010) no one has been to all 254 of these points.