The hedgehog is a small insectivorous beast, also called an “urchin” or “herrison”. When faced with danger it would roll itself into a ball, exposing only its spines; so it came to be a symbol of caution. It is a period charge, found in the canting arms of Herries, c.1275 [ANA2 120]. The hedgehog is statant by default, as in the illustration; its “proper” tincture is brown, with a white face and belly.
Of the period depictions of hedgehogs in armory, one curious example shows it with grapes impaling its spikes, rather like an animated hors d’oevre tray! It’s found this way as the crest of Claxton, 1561 [Gwynn-Jones 33].
Similar to the hedgehog is the “porcupine”, with longer and fewer quills which were held to be poisonous. It too is a period charge, dating to 1445 in the arms of Eyre [Parker 473]. A crowned porcupine was the badge of Louis XII, d.1515 [Neubecker 210].
Rúadnat ingen Diarmada bears: Or, three hedgehogs statant gules.
Judhael de Cornouailles bears: Argent, a chevron gules cotised, in base a porcupine statant sable.
Mergriet van Edelare bears: Gules, a hedgehog statant argent its quills impaling grapes purpure.