Although the fairy tale is a distinct genre within the larger category of folktale, the definition that marks a work as a fairy tale is a source of considerable dispute. The term itself comes from the translation of Madame D'Aulnoy's Conte de fées, first used in her collection in 1697. Common parlance conflates fairy tales with beast fables and other folktales, and scholars differ on the degree to which the presence of fairies and/or similarly mythical beings (e. g. , elves, goblins, trolls, giants, huge monsters) should be taken as a differentiator. Vladimir Propp, in his Morphology of the Folktale, criticized the common distinction between "fairy tales" and "animal tales" on the grounds that many tales contained both fantastic elements and animals. Nevertheless, to select works for his analysis, Propp used all Russian folktales classified as a folklore Aarne-Thompson 300-749 – in a cataloguing system that made such a distinction – to gain a clear set of tales. His own analysis identified fairy tales by their plot elements, but that in itself has been criticized, as the analysis does not lend itself easily to tales that do not involve a quest, and furthermore, the same plot elements are found in non-fairy tale works.