Are Petrophytum and Townsendia both in the rose family?
Petrophytum Petrophytum (orth. var. Petrophyton) is a small genus of plants in the rose family known as the rock spiraeas or rockmats. These are low mat-forming shrubs which send up erect stems bearing spike inflorescences of flowers. The brushy flowers are white and have many stamens and hairy, thready pistils. Rockmats are native to western North America.
Halesia tetraptera Halesia tetraptera, commonly known as the common silverbell or mountain silverbell (or Carolina silverbell; syn. "Halesia carolina" auct. non L.), is a species in the family Styracaceae, native to the southeastern United States. It is cultivated as an ornamental tree.