What did Simon discover in the forest ?

In Chapter Nine, Simon's fit passes into the weariness of sleep. Waking up, Simon speaks aloud to himself, questioning what he will do next. His nose bleeding, he climbs farther up the mountain, and in the dim light, catches sight of the Beast. This time, however, he recognizes it as the body of the man who parachuted onto the island. Overwhelmed with disgust and dread, Simon vomits. He realizes that he must inform the other boys of their mistake, and he staggers down the mountain toward Jack's camp to tell them what he has found.