I remember seeing an illustrated dictionary or encyclopedia of fantasy stories or fairy tales in a book store during the period of 1961-1968.
I remember a few details about some of the entries.
The entry on dragons began: "Dragons drag." And it accused dragons of basically doing nothing despite their great powers.
The entry on dukes mentioned that dukes were almost kings, so close to being kings that the difference made them bitter and they were always plotting against kings.
It was mentioned that wizards usually lived in towers.
And I remember an illustration, a chart with specimens of the various fantasy or fairy tales species side by side for identification.