"...It's important to have a job that makes a difference, boys. That's why I manually masturbate caged animals for artificial insemination..."
A basement of dunces?
An index of illiterates*?
*Those individuals who find it challenging to truly comprehend "reading".
I forget where, but one thesaurus has "California" (or something close to it) as a synonym for compilation, collection, or aggregation or something. Considering how many members are Californians, I would think that that would be an appropriate use of the term for some subset of "all head-casers".