In later versions of this poem, Coleridge added a Latin epigraph and marginal notes. I have heard that some scholars consider these notes to be an integral part of the poem. Their tone is scholarly, but their content seems in places unmistakably silly. They certainly changed my impression of the poem. I cannot alter hodgepodge's text by inserting these notes, but I can reproduce the epigraph and a translation, reproduced from Ian Johnston's e-text collection:

Facile credo, plures esse Naturas invisibles, quam visibiles in verum universitate. Sed horum omnium familiam quis nobis enarrabit? et gradus et cognotiones et discrimina et singulorum munera? Quid agunt? quae loca habitant? Horum rerum notitiam semper ambivit ingenium humanum, numquam attigit. Juvat, interea, non diffiteor, quandoque in anima, tanquam in tabula, majoris et melioris mundi imaginem contemplari: ne mens assuefacta hodiernae vitae minutiis te contrahat nimis, et tota subsidat in pusillas cogitationes. Sed veritati interea invigilandum est, modusque servandus, ut cera ab incertis, diem a nocte, distinguamus. (T. Burnet, Archaeol. Phil.)

I easily believe that in the universe the invisible Natures are more numerous than the visible ones. But who will clarify for us the family of all these natures, the ranks and relationships and criteria and functions of each of them? What do they do? In what places do they dwell? The human mind has always searched for the knowledge of these matters but has never acquired it. Meanwhile, I do not deny that it is from time to time useful mentally to picture in the mind, as on a tablet, the image of a larger and better world, so that our minds, preoccupied with trivial matters of everyday life, does not shrink excessively and subside entirely into petty ideas. We must however be careful about the truth and keep a sense of proportion, so that we may discrimate between the certain and uncertain, day from night. Thomas Burnet, Archaeologiae philosophicae

Coleridge, "The Rime of the Ancient Mariner". http://records.viu.ca/~johnstoi/poems/coleridge2.htm - accessed Nov 18, 2010 (link fixed by an editor)