▁for ▁military ▁service , ▁was ▁held ▁in ▁July ▁ 3 7 , ▁and ▁a ▁con gi arium ▁of ▁ 7 5 ▁den ari i ▁was ▁distributed ▁to ▁each ▁citiz en ▁by ▁Cal ig ula . ▁Comment s ▁by ▁T ac it us ▁and ▁Su eton ius ▁that ▁he ▁was ▁still ▁a ▁child ▁this ▁year , ▁despite ▁the ▁fact ▁that ▁he ▁was ▁ 1 8 , ▁may ▁refer ▁to ▁his ▁mental ▁development . ▁This ▁would ▁explain ▁why ▁he ▁had ▁not ▁yet ▁received ▁the ▁to ga ▁of ▁man hood . ▁ ▁It ▁is ▁possible ▁that ▁his ▁ad option ▁meant ▁an ▁official ▁recognition ▁and ▁accept ance ▁as ▁Cal ig ula ' s ▁he ir . ▁Phil o ▁saw ▁this ▁as ▁a ▁p loy ▁to ▁put ▁Gem ell us ▁under ▁Cal ig ula ' s ▁pat ria ▁pot est as ▁( power ▁of ▁a ▁father ), ▁and ▁perhaps ▁to ▁conv ince ▁the ▁Senate ▁to ▁go ▁along ▁with ▁null ifying ▁T iber ius ' ▁will . ▁A do pt ing ▁Gem ell us ▁gave ▁Cal ig ula ▁time ▁to ▁deal ▁with ▁the ▁succession ▁issue . ▁ ▁Death ▁Following ▁an ▁ill ness ▁suffered ▁by ▁Cal ig ula , ▁Gem ell us ▁was ▁put ▁to ▁death ▁in ▁late ▁ 3 7 ▁or ▁early ▁ 3 8 . ▁Cass ius ▁D io ▁places ▁his ▁death ▁and ▁that ▁of ▁Cal ig ula ' s ▁father - in - law ▁Marcus ▁Jun ius ▁Sil anus ▁in ▁the ▁events ▁of ▁late ▁ 3 7 . ▁Their ▁rep lac ements ▁in ▁the ▁Ar val ▁Bre