ARGO, the large Ptolemaic constellation (q.v.) of the south ern hemisphere (cargo, a ship), which was subdivided by Sir John Herschel (q.v.) into Vela (sails), Puppis (poop), and Carina (keel) (qq.v.). Some writers however still refer to it as one complete constellation, e.g., the variable star j Carinae is also called 77 Argus.