On many BEATA coins from Trier, Constantine II is depicted holding a parazonium, which is a dagger with an eagle's head for the pommel cap. It has been correctly described for many years, but it continues to also be incorrectly described.
I thought it would be interesting to look at some literature and see how the object is described -- listed below chronologically.
2014 Roman Coins and Their Values by David Sear calls it a mappa.
2004 -- Die römische Münzserie Beata Tranquillitas in der Prägestätte Trier 321-323. by Alten and Zschucke call it a Kurzschwert (Lat.: Parazonium).
1982 Le Monnayage de L'Atelier de Lyon: De La Reouverture de L'Atelier en 318 a la Mort de Constantin (318- 337). by Pierre Bastien calls it a parazonium.
1982 Roman Imperial Coins in the Hunter Coin Cabinet describes it as a mappa.
1967 Roman Imperial Coinage VII describes it as a mappa.
1961 Die Spätrömische Kupferprägung: Ein Bestimmungsbuch Für Schlecht Erhaltene Münzen by Guido Bruck. This book is mostly line drawing and it shows a parazonium with a clear depiction of the eagle-headed pommel cap.
1908 Numismatique Constantinienne by Maurice describes it as a mappa.
