
George James Welborne Agar-Ellis, PC, FSA, FRS, 1st Baron Dover (1797-1833)
He was the son of Henry Welbore Ellis, 2nd Viscount Clifden of Gowran and Lady Caroline Spencer daughter of Sir George Spencer, 4th Duke of Marlborough and Lady Caroline Russell.
He married Lady Georgiana Howard, daughter of Sir George Howard, 6th Earl of Carlisle and Lady Georgiana Dorothy Cavendish.
He was the son of Henry Welbore Ellis, 2nd Viscount Clifden of Gowran and Lady Caroline Spencer daughter of Sir George Spencer, 4th Duke of Marlborough and Lady Caroline Russell.
He married Lady Georgiana Howard, daughter of Sir George Howard, 6th Earl of Carlisle and Lady Georgiana Dorothy Cavendish.

F 9784 [1814]
Arms: quarterly: 1 and 4, argent on a cross sable five crescents argent; 2 and 3, azure a lion rampant argent.
Crest: a demi-lion rampant.
Supporters: Dexter, a greyhound collarded, the collar charged with three crescents; sinister a lion, with a crest.
Motto: Non hæc sine numine
Lord Dover used 2 other bookplates (F9782, F9783) and another, bearing his title of Lord Dover (after 1831) with Ellis, quartering Agar, impalling Howard (F9775). He also used superlibris stamped on the binding covers of his books see, Binding stamp of George Agar-Ellis, Baron Dover
Sources: http://www.thepeerage.com/p1163.htm#i11622
http://www.sussexexpress.co.uk/seaford-in-the-past/MP-who-laid-foundations-of.2919524.jp