#OnThisDay in 1958 #TheLegionOfSuperHeroes debuted in @DC.com #AdventureComics #247 when #SaturnGirl #LightningBoy #CosmicBoy #ASuperHeroClubFromTheFuture visit #Superboy informing him #heInspiredTheirUnion after putting him thru #aSeriesOfTests & #offeringHimMembership turns #seriesLeadFeature 1963