After posting about some of W. W. Denslow's endpaper designs, it's only fair to look at some of John R. Neill's work. One of the great things about the Oz series is the quantity of illustrations, which spill over to preliminary pages and onto the endpapers of the books. Only one Oz book was published without pictorial endpapers, The Wishing Horse of Oz from 1935.
Neill found a number of ways to incorporate the Oz logo into quite a few of his endpaper designs. The first two shown are the early ornate color endpapers seen in Dorothy and the Wizard and The Road to Oz. Oz titles through Tik-Tok of Oz all included color in the endpapers, as part of the unique features of the books.
Beneath these, we see Grampa in Oz, using the logo as a border element, and The Hungry Tiger of Oz where the Oz logo seems to have been dropped into the picture for no particular reason.
In the four examples above, Neill used simple bold images featuring the logo and characters from the stories - The Lost King of Oz, Jack Pumpkinhead of Oz, The Silver Princess in Oz and Lucky Bucky in Oz.
Below, The Cowardly Lion of Oz uses it subtly, as decoration on the lion's blanket, and The Giant Horse of Oz has one of my favorite designs - a wild game of hoops, featuring the logo in various sizes!