Arms of Trevelyan: "Gules, a demi-horse argent hoofed and maned or issuing out of water in base proper" (blazon per Debrett's Peerage, 1968, p.798); "Gules, the base barry wavy argent and azure a demi-horse issuant of the second maned and hoofed or" (blazon per Vivian, Lt.Col. J.L., (Ed.) The Visitation of the County of Devon: Comprising the Heralds' Visitations of 1531, 1564 & 1620, Exeter, 1895, p.736). Note that the top bar wavy is argent, per the Vivian blazon, possibly representing spume on a rough sea.