German, dated 1871, slide engraved ‘II Diat-Typen-Platte Deckglasdicke 1/9th mmtr, J. D. Möller Wedel in Holstein Germania 1871’ with a single groups of diatoms in a square arrangement, in a leather case with gold wording to the lid which reads ‘J.D. MÖLLER’S DIATOMACEEN-TYPEN-PLATTE’, with blue velvet lining and cream silk to the lid, with a large printed single-sheet catalogue titled 'Diatomaceen-Typen-Platte II, Catalogue of the Diatomaceae, according to the classification of Mr A Grunow, Vienna' and dated October 1871.