MEMO is an educational charity dedicated to building an ongoing memorial to extinct species. The memorial will be a stone monument bearing the images of all the species of plants and animals known to have gone extinct in modern times. It will incorporate a bell to be tolled for all extinct species, including the great many ‘unknown’ species which it is believed perish each year unseen by scientists. The bell will be tolled on the International Day of Biodiversity on 22nd May each year. On the outside of the monument there will be marvellous patterns of simple units based on the forms of microorganisms to be carved by thousands of secondary school children.