CORNELIASON CREEK. Corneliason Creek rises a mile south of Bells in extreme east central Grayson County (at 30°34' N, 96°24' W) and runs northwest for eight miles to its mouth on Mill Creek, three miles southwest of Ambrose (at 33°39' N, 96°26' W). The surrounding flat to rolling prairie is surfaced by dark, commonly calcareous clays and sandy and clay loams that support mesquite, pine, mixed hardwood trees, cacti, and various grasses.