Coat of arms of the bishop Mark William O’Connell, Auxiliary Bishop of Boston.
Blazon: Per saltire Argent and Barry Wavy of six Argent and Azure, In chief a stag's head cabossed Gules, in fess two mullets Or, and In base a rolled parchment scroll Proper sealed Gules and corded Vert. On a chief Azure fretty Or a fish naiant Argent.
Motto: «INVENIMUS MESSIAM»
Reference:

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