There are four basic types of iconographic representations of the cross: the crux quadrata, or Greek cross, with four equal arms; the crux immissa, or Latin cross, whose base stem is longer than the other three arms; the crux commissa, in the form of the Greek letter tau, sometimes called St. Anthony’s cross; and the crux decussata, named from the Roman decussis, or symbol of the numeral 10, also known as St. Andrew’s cross for...