This Brothers & Sisters photo contains
boater, leghorn, panama, panama hat, sailor, skimmer, straw hat, fedora, felt hat, homburg, stetson, trilby, dress hat, high hat, opera hat, silk hat, stovepipe, top hat, topper, and beaver.
There might also be
long trousers, long pants, pith hat, pith helmet, sun helmet, topee, topi, and slacks.