 The name comes the Greek hydnum meaning spongy plant or fungus . The British Mycological Society , in their recommended list of common names for fungi in the United Kingdom , name Hydnellum fungi in the form " descriptor word " plus " tooth " , such as " gold tooth " ( H. auratile ) , " zoned tooth " ( H. concrescens ) , and " velvet tooth " ( H. spongiosipes ) . 
