Latex replica, of a mould in fine sandstone, of a trilobite eye (Dalmanitina socialis, Ordovician Bohemia) which shows details of the inner surface of the lenses. In life, a thin calcitic bowl was attached to this inner surface so that the correcting doublet gave a sharp image. HTML The image represents an area approximately 630 µm wide. Image courtesy of Prof. Euan Clarkson, Geology and Geophysics, University of Edinburgh. This article was published on 2024-07-01