Final answer:
The Greek Chapel in the Catacomb of Priscilla consists of a tufa dugout with round arches, barrel vaulted ceilings, burial niches styled as dining couches, and decorated with frescoes and mosaics.
Step-by-step explanation:
The form of the catacomb in the Greek Chapel from the Catacomb of Priscilla in Rome, Italy, is a dugout of tufa with round arches and barrel vaulted ceilings. During the establishment of Christianity, these catacombs served not only as burial places but also as spaces to display religious artwork.
The catacombs were carved out of soft tufa rock and featured burial niches styled after ancient dining couches (klinai). The artwork within these catacombs includes frescoes and mosaics, showcasing early Christian symbolism and religious icons, sometimes embellished with gold leaf for added reflection and adornment.