Marvelous post from Daniel Mitsui on what I’d say is a little-known element of church decor, but was actually common before the relatively modern tabernacle was developed:

Eucharist Doves have been mentioned in several discussions on liturgically-minded Catholic Blogs, but remain unfamiliar even to most traditional Catholics. Essentially, the Eucharist Dove was a stylized pyx, which was used to reserve the Blessed Sacrament above the altar of a medieval church. They fell from fashion during the Counter-Reformation, when the modern tabernacle that St. Charles Borromeo promoted became common.

Several pictures and links to more information. Via Don Jim who’s mentioned in a WaPo article on blogging clerics in the DC-area!