Colobium (κολόβιον) was a tunic with very short sleeves only, and fitting closely about the arm. The tradition was that Sylvester, bishop of Rome, ordered that deacons should wear dalmatics in offices of holy ministry, in place of the colobia, which hlad previously been in use. From this circumstance of the colobium being regarded as thle special vestment of a deacon, it is sometimes called lebiton (i.e., leriton) or lebitonarium, a word which reappears in ecclesiastical Greek of the 5th and later centuries (λεβιτών). The monastic colobium in Palestine, if not elsewhere, had upon it a purple "sign," probably a cross, used, perhaps, as a mark of service under Christ. Examples of the Greek colobium may be seen in the ancient mosaics of the 4th century, in the church of St. George at Thessalonica.