Controlled vocabularies combine genre and form because there is no clear-cut way to differentiate these and there is very little point in arguing about which list a term should be in.
Quoting from the MARC format 655, which covers genre, form, and physical characteristics
"Examples of genre terms for textual materials are: biographies, catechisms, essays, hymns, or reviews. Examples of form and physical characteristic terms are: daybooks, diaries, directories, journals, memoranda, questionnaires, syllabi, or time sheets. "
Well, that's nice--diaries are only form/physical characterics?! So, my *memoir* can be a genre, but my *diary* can only be a form? Surely you want memoirs and diaries to be on the same list of options.
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