Macroforms are the literary constructions which we might consider anthologies composed of smaller building blocks of lemmata and microforms. These smaller forms are rhetorically built up into larger forms to make "new" literary works or commentaries on prior works.

These can be compared to Western rhetorical traditions going back to Seneca the Younger in Epistulae morales

"We should follow, men say, the example of the bees, who flit about and cull the flowers that are suitable for producing honey, and then arrange and assort in their cells all that they have brought in; these bees, as our Vergil says, 'pack close the flowering honey | And swell their cells with nectar sweet.' "

He's essentially saying, read the best, take their thoughts and ideas, consume them, make them your own."

Generations later in ~430 CE, Macrobius in his Saturnalia repeated the same idea and even analogy (he assuredly read Seneca, though he obviously didn't acknowledge him):

"You should not count it a fault if I shall set out the borrowings from a miscellaneous reading in the authors' own words... sometimes set out plainly in my own words and sometimes faithfully recorded in the actual words of the old writers... We ought in some sort to imitate bees; and just as they, in their wandering to and fro, sip the flowers, then arrange their spoil and distribute it among the honeycombs, and transform the various juices to a single flavor by some mixing with them a property of their own being, so I too shall put into writing all that I have acquired in the varied course of my reading... For not only does arrangement help the memory, but the actual process of arrangement, accompanied by a kind of mental fermentation which serves to season the whole, blends the diverse extracts to make a single flavor; with the result that, even if the sources are evident, what we get in the end is still something clearly different from those known sources."

(cross reference: https://hyp.is/mCsl9voQEeuP3t8jNOyAvw/maggieappleton.com/echo-narcissus)