A detailed proposal for a Fantasy Fiction Dewey Decimal Classification system, as fantasy stood in 1964. An example…

12. Unrationalized permutations, whimsies.
    12.5 Animals that talk.
    12.6 Unliving things personalized.

I presume things have moved on, both in terms of fine-grained classification and in fantasy’s crossover sub-genres. But it’s still an interesting snapshot of the field at that point in time.