Shield of the House of Medina Sidonia.
The Shield of the House of Medina Sidonia, on azur field, shows the arms of the lineage Perez de Guzman, which are two boilers stamped in gold and gules, gringoladas of seven serpents in sinople, placed on the pole. The border carries the arms of the House of Castile and Leon, with nine pieces of gules, with gold castles, alternating with nine pieces of silver with gules lions.
To the bell, ducal crown with summit that brings to Guzman the Good in attitude of throwing a dagger from the castle of Tarifa, all crowned by phylactery with the motto of the house nobiliaria: Praefere Patriam Liberis Parentem Decet (A father must to the fore, a dragon in sinople subdued, representing the serpent of Fez, and to the flanks the columns of Hercules, with the Non Plus Ultra. Notes
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