HARD OUTER LAYER

Went to St.Simon, yesterday and there were countless of Jellyfish on the shores off Neptune Park. My son said it looked like a death field every step we took they were washed out/ we even saw one fighting to stay in the water. We touched thefirst one with a stick since we know they can sting like crazy! Expected it to be soft but it was hard. Also, starfish on the other side of the island