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[Jorge_Stolfi]

And I certainly don't understand the category "Recipes"—is that generally accepted, too? And for what reason?

Another name sometimes used for that section is "Starred Paragraphs"n, which does not require any interpretation. 

But that name is long and inconvenient.  The parags could be anything, but, given that the rest of the book seemed to be about medicine (the Herbal was obviously a herbal, and the Pharma section has those jars in the margin), recipes seemed to be a good guess.  There are many examples of manuscripts from that time with lists of short recipes for medicines or foodstuffs.  (Culpeper's herbal too has two main sections: a list of medicinal plants, with history, properties, etc, and a list of recipes of remedies that one can make from those plants.)   Hence the conventional name "Recipes".

(It turns out that the correct name for that section is "Remedies", that is, medicinal substances -- what pharmacists of the time called "simples".  But who cares about the truth?)

All the best, --stolfi