(4) Roman cavalry is attested under Marius himself at the Battle of Vercellae (101 BC). Jeremiah McCall argues that legionary cavalry was probably abolished during the Social War (91–88 BC). But even this is uncertain. It is widely believed that Julius Caesar's legions in the Gallic war had no attached cavalry. This is based on an incident in 58 BC when Caesar, who needed a large cavalry escort to meet the German king Ariovistus, ordered his Gallic allied cavalry, whom he did not yet fully trust, to hand their horses to soldiers of the 10th Legion, which was from that time jokingly nicknamed "equestris" ("the mounted legion"). However, according to Plutarch, 7,000 cavalry "from the flower of Rome and Italy" served in Pompey's army at the Battle of Pharsalus (48 BC).