For posterity and hopes of someone recognizing this family I'm posting my findings to this forum.
On the 1871 census of Merthyr Tydfil, Glamorganshire
Wm. Davis ae 28 b. Merthyr, wife Ann ae 27 b. Merthyr, son Wm. ae 6 b. Merthyr, and son Evan ae 4 b. Merthyr
On the 1881 census of Cwmda, Maesteg, Glamorganshire
Ann Davies ae 36 married, Head, b. Merthyr, son William ae 16 b. Merthyr, son Evan ae 14 b. Merthyr, dau Mary J. ae 6 b. Maesteg, son David ae 4 b. Maesteg, dau Clarissa ae 2 b. Maesteg
Mary Jane Davis Hurl d. 26 May 1944 Steubenville, Jefferson Co., OH; resided 723 Allegheny St. Follansbee, Brooke Co., WV, ae 69, married, White, Housewife, b. 7 Aug., 1874 Maesteg, South Wales, buried 24 May 1944 Riverview Cem., Martin's Ferry, OH, dau. of William H. Davis, b. Wales, and Anna Morgan, b. Wales, married to Stephen Hurl
1900 census Pease Twp., Martins Ferry City Ward 1-2, Belmont Co., OH, district 10
Stephen Hurl ae 26, married, white, head, married 4 yrs., b. OH of OH b. parents, b. Jan., 1874, Mary Hurl, wife ae2 26, b. Wales, 2children, 2 living, b. Sept., 1874, immigrated abt. 1882, dau. Mabel ae 3, b. OH Feb., 1897; son William Hurl ae 1, b. OH Feb., 1999, bro-in-law Robert Davis b. OH; sis-in-law Clara C. Davis b. Wales
Rob't M. Davis b. 17 Jul., 1882 Aetnaville, Belmont Co., OH, son of W. H. Davis & Anna Morgan
Searching for connections to this family, especially Wm. & Ann (Morgan) Davis' parents in Merthyr on 1841, 51 and '61 census, and siblings to Wm. & Ann.