It is sometimes asserted that Pyxis is one of the parts into which Lacaille divided the former Argo Navis, but that is not the case. Lacaille divided Argo into three –Carina, Puppis and Vela. Pyxis is an additional constellation, and Lacaille showed it separately on his map and in his catalogue. The four stars that Lacaille labelled Alpha to Delta Pyxidis had actually been catalogued by Ptolemy as lying in or around the mast of Argo, but Bayer did not assign letters to them so Lacaille evidently felt free to appropriate them for his new constellation.
There are no legends associated with it – indeed, the magnetic compass was completely unknown to the ancient Greeks.