This Fine Art photo contains
boater, leghorn, panama, panama hat, sailor, skimmer, straw hat, fedora, felt hat, homburg, stetson, and trilby.
There might also be
dress hat, high hat, opera hat, silk hat, stovepipe, top hat, topper, beaver, porkpie, porkpie hat, pith hat, pith helmet, sun helmet, topee, and topi.