Berlin, Königlichen Akademie der Wissenschaften zu Berlin, G. Vogt, 1873-1875. Two parts in two. 4to (27.5 x 22.2 cm). 496 [131-399; 1-226] pp.; 42 [I-XII; I-XXX] partly tinted lithographed plates, and one coloured folded world-map, six large, folded tables. Original printed boards and matching later boards.

This is a rare complete set of the Studien, both published in the academy's Abhandlungen. Together, it forms an important contribution to the start of micropalaeontology, in particular the study of the sea bottom. It is more or less a continuation of Ehrenberg's famous Mikrogeologie and deals mainly with skeletons of "lower" organisms such as diatoms, and Foraminifera. The illustrations are excellent, those in the first (1873) part are partly coloured or tinted. The second part contains a Nachtrag, covering pp. 169-226. Nissen only quotes the famous Mikrogeologie but not these Mikrogeologische Studien. Some foxing to the tables and plates of the second part. A few japanese paper repairs to some text leaves of the first part, otherwise a good set. Nissen ZBI, 1245; Zittel p. 326.