The boys went out hunting and they are looking really scruffy “yet half, much to long, tangled here and there”. They have gone to hunt or find the big pig the sow.
This could be to have a big feast and to make sure that they all eat. It was hot that day and Ralph was searching for Simon. Ralph pretended that he hit the boar.
Jack came back to everyone to tell them that it was a boar not a beast.