Zoological reference books of the Middle Ages were called bestiaries. They included both famous and legendary animals, or those invented by travelers. The famous writer Kir Bulychev set himself the goal of creating a bestiary, which includes only fictional animals, from the monsters of Ancient Greece to the fairy-tale creatures of our days. In order to gather such a strange company, the author turned to fairy tales, myths, and fantasies from around the world. Therefore, in the bestiary there was a place for Japanese merman, Chinese werewolves, Russian brownies and goblins, Norwegian trolls and even Tyanitolkai, who was invented by Korney Chukovsky.