Prodromus in systema historicum testaceorum
A late eighteenth-century Viennese catalogue of mollusc shells, published in 1795 by Ignaz Alberti's widow and written by Joachim Spalowsky for natural history students and collectors. Its pages are hand-coloured plates of shells arranged in numbered groups, with each specimen drawn in fine detail against a pale cream ground, giving a designer a model of classical scientific botanical-style plate layout and soft watercolour shading.



