English: Parietal relative sizes among specimens of Pentaceratops, and related chasmosaurines. Parietals of chasmosaurine taxa mentioned in the main text, all in dorsal view and to scale with each other to show relative size. Taxa shown in stratigraphic order (with the exception of (E), SDMNH 43470). (A) Utahceratops gettyi referred specimen UMNH VP-16671; (B) cf. Pentaceratops sternbergii referred specimen AMNH 1625. Aff. Pentaceratops sp. referred specimens (C) UKVP 16100; (D) NMMNH P-37880, and (F) MNA Pl. 1747; (E) Aff. Pentaceratops sternbergii referred specimen SDMNH 43470; (G) Navajoceratops sullivani holotype SMP VP-1500; (H) Terminocavus sealeyi holotype NMMNH P-27468. (I) Chasmosaurinae sp. “Taxon C” specimen NMMNH P-33906. ep, epiparietal loci numbered by hypothesized position (no epiossifications are fused to this specimen); mb, median bar. Line drawings adapted from Longrich (2014), and Sampson et al. (2010). Scalebar = 10 cm.