The Stag Beetle is named for the huge jaws (antlers) of the male,which are used to fight rival males in the breeding season.The female has normal jaws. Size is variable, female up to 30 - 40mm, male to 50 mm - 70. Can be seen in parks with old trees, and old forrests. Adults feed on sap oozing from wounded trees. When I saw this beetle it was in deep shade, and I didn't want to disturb it in case it flew away, so I had to lighten the photos considerably, which accounts for the bluish tinge. Their true colour is black and chestnut. The photos are not good, but it's an interesting beetle to show you.