Unpublished paper, 'On the structure of the iris and membrana pupillaris' by Arthur Jacob Jacob writes on whether or not there is any muscular element to the structure of the iris and describes his observations with this view. He also discusses the phenomenon of the membrana pupillaris [persistent pupillary membrane], an anomaly of the eye that is supposed to disappear prior to birth, but that remains present in some humans after birth. He explains how to dissect an eye in order to view its parts in the same way that he did for his paper. Minor corrections and deletions appear throughout in ink and graphite. Subject: Anatomy Communicated by James Macartney. Read to the Royal Society 27 June 1822. [1822]