This The Monkees foto contains
boater, leghorn, panama, panamahut, seemann, skimmer, hut stroh, bootsfahrer, bein, strohhut, livorno, panama-hut, filzhut, homburg, stetson, trilby, fedora, stetson trilby, kampagne hut, and kampagnenhut.
There might also be
kavalier hut, schlapphut, slouch hut, and kavalier hut schlapphut.