Looking through it, I see 3 or 4 of the patterns could be slouchy hats, yep. They're not specifically called that, the author has given each hat a specific name, but I would say that those ones would be "slouchy" on anyone. I'll see if I can get a couple of photos to add...
Okay! Updated to add 3 pictures from the book; the hats show being worn with all of the person's hair up inside it; without the hair they would slouch nicely. :)