Attached are two photos of mosaics with similar symbols. One is of the Miracle of the loaves and fishes from the top register of the nave wall (above the clerestory windows) of Sant' Apollinare Nuovo, Ravenna, ca. 504. The other one is called the parting of Lot and Abraham in the nave of Santa Maria Maggiore, ca. 432-440. Do you have any idea what is symbolized by the things that are circled? It's found in both mosaics.
Here are the two photos the reader sent in.
There are other variants upon this:
Feel free to use the comments.
