Hedgehog fungus

A new fungi for me this morning. I found a dozen or more of these in the woods. Unlike most of the the other fungi I've seen so far these have spines on the underside rather than pores or gills. I assume that's how they get their common name of the Hedgehog Fungus (presuming I've correctly identified it). The caps were quite varied in colur, some were very white and others more of a pale apricot, perhaps they change colour with age.