46. Spider World 1: The Desert, by Colin Wilson.

The Desert is the first of six Spider World books. They follow Niall, a young boy who has an unusual ability to sense the willpower and mental presence of the spiders, their current overlords, as he and his family hide in caves in a treacherous desert. When they travel to return his uncle's widow to her people, Niall learns more about his people and his place within the world.

This book was one I was hesitant to read, as I'm not a fan of spiders and didn't really want to give myself horrifying nightmares. However, I was reasonably pleasantly surprised to find that this is definitely not so much a horror book, but fantasy adventure with a little sci fi thrown in, The spiders are presented in a truthful-seeming shape, and the plot moves forward pretty steadily.