Crumillospongia
Crumillospongia is a genus of middle Cambrian sponges known from the Burgess Shale and other localities from the Lower and Middle Cambrian. Its name is derived from the Latin crumilla and spongia, a reflection of its similarity to a small leathery money purse. That is, it has a saclike shape, and its wall has holes of two sizes, with a well-developed internal canal system.
