I read this in middle school approx. 35 years ago. Looking for a short story about a scientist from a museum who falls into a hole and gets trapped while looking for rare giant spiders. It was in a jungle setting possibly So. america. The spiders returned to the hole (their home base? and crawled all over him especially when it started to rain and the hole filled up with water. He eventually is able to burrow or tunnel out of the hole. .