Although printed forty years ago in a once well-known textbook, certain marginalia written by Coleridge in a copy of Descartes' Opera Philosophica have never, I believe, been the subject of any comment. They are, however, of considerable interest, aside from that of a sentimental kind, for of four notations—one a mere reference for later transcription—two have relationship, hitherto unnoticed as far as I am aware, with a paragraph in the Biographia Literaria, and the reference is to a passage part of which was quoted as a volume motto in The Friend.