Thanks for the tracings from [Johan Christian] Fabricius' 1783 memoir on the hearing of insects; notes that Fabricus does not seem to have looked into the internal structure of the hearing organs of crayfish. Notes a dissertation by Mr Minasi titled "Dissertazione dei Timpanetti dell'udito scoperti nel Granchio Paguro" (1775) that may predate Fabricius' work. [Giovanni Antonio] Scopoli's successor at University of Pavia is Brusatti, previously Professor of Chemistry at the Theresian College in Vienna.