Which one of Henry VIII wives did Henry VIII think was ugly?

Historically speaking, Henry VIII thought Anne of Cleves (Anna von Kleve) to be ugly. Realistically, what we see is a disappointed man beyond his youth who accosted his wife-to-be during a bear baiting and kissed her, while dressed in poor clothing and pretending to be no more than a burgher. Of course Anne spurned him and spat his spittle out of her mouth which certainly dismayed him; he finally realized that he was no longer a young man or desirable to a young woman. They married, per the agreement, but were declared to be no longer man and wife months later, when Henry's appetite was drawn by Katherine Howard.

Anne of Cleves was reportedly called the 'Dutch Mare' by Henry during one of his rampages.