Sir Banastre's "arms" (i.e. heraldic device), as drawn by Leanne Shaw. In heraldic terms, it reads, "Gules, a chevron erminois between three cinquefoils or" according to Burke.

Tarleton's baronetcy is listed in Burke, John & Burke, John Bernard; A Genealogical And Heraldic History Of The Extinct And Dormant Baronetcies Of England, Ireland And Scotland; (London: Burke's Peerage, 1964), p518, which gives portions of his family lineage back to the 1680s.

Note that this is not "the Tarleton family crest," as it is sometimes called. It was created for Sir Banastre after he was granted his baronetcy -- according to Burke's, on Nov. 6, 1818, which is presumably the date it was registered -- and became extinct upon his death. When his great-nephew (the son of his nephew and sometime aide-de-camp Thomas) became (Admiral) Sir John Walter Tarleton, K.C.B., his own arms incorporated the same design in the first and fourth quarters.

Unfortunately, we don't know the origin of the image on which Leanne based this drawing. Michael Estacio has sent along the comment that "If the blazon is correct, the chevron in Tarleton's coat of arms should have black ermine spots (erminois)." The image Leanne used shows the same (spot-free) chevron, so the best I can do is note the discrepency, pending further research.

Sir John's crest is slightly different from the one shown here ("a mural crown thereon a leopard's face all between two ostrich feathers proper") but he used the same motto ("post nubila Phoebus", meaning "After clouds, sunshine"). Presumably he borrowed both from his great-uncle's heraldry, but I haven't confirmed that.