A capsule and spores. Each spore is about 50 microns in diameter. This species can only be reliably separated from Ephemerum serratum by examination of the spores, but this is a fun and straightforward thing to do if you've got a compound microscope. In E. minutissimum, one of the smallest mosses in the UK, the spores are finely roughened and often have a persistent 'veil' surrounding them (E. serratum spores are more coarsely roughened and typically lack the veil). From an old anthill in a churchyard in Sarratt, Herts, 12/2/19.