When in Rome

This is something of a puzzle. What are the parallels that George Bain sees in these designs from Rome and the British Isles? There is a simple interlaced border at the top of the main subject but he doesn’t really connect it with the other drawings.

Perhaps Bain is interested in the pair of peacocks facing each other? This is in a mosaic at St Maria in Trastevere, Rome. There is another pair in his extract from a folio in the Book of Kells, although they’re looking backwards. But why does he also draw the two saints and lions from the top of the Nigg cross-slab in Easter Ross?

Nevertheless this another superb example of Bain’s illustrative skills.  It is also one of a small number of drawings that refer to designs from the Roman period.