Reconstruction of the sponge, Vauxia densa, from the Middle Cambrian Burgess Shale of British Columbia. These tall, tubular sponges were probably the largest sponges in the Burgess Shale fauna. They have been associated with the onychophoran, Aysheaia, which may have been a sponge predator. The size ranges from 60 to 140 mm. tall and about 22 mm. in diameter.