From the foreword:
"The Friedrich-Hustedt-Arbeitsplatz für Diatomeenkunde at the Alfred-Wegener-Institut in Bremerhaven (BRM) holds among many others also slides bearing the labels of Heinrich Heiden (1857-1925). Quite a number of these are slides with material from the German South Polar Expedition 1901-1903. As former curator of this collection I was well aware of this fact, but it was only fairly recently that I realized that there was an almost complete series of slides containing the original material of the important publication of Heiden & Kolbe 1928.
As far as I could find out the diatom collection of Heiden must be considered to be lost. Professor Pankow of Rostock does not know anything about its fate, nor did Hustedt, as he repeatedly wrote in his Kieselalgen (1927-1966). The residues of the samples of the South Polar Expedition were deposited at the Botanical Museum in Berlin, as Kolbe remarks (Heiden & Kolbe 1928, p. 453), and these holdings were destroyed during World War II. The Heiden slides in the Hustedt Collection are therefore evidently the last ones existing today.
Realizing this situation, I felt there was obligation and responsibility to study more closely Heiden's taxa, to photograph and to lectotypify them wherever possible. Since Antarctic diatoms have found much attention recently, this was another reason to publish an account of Heiden's diatom types in Heiden & Kolbe 1928. In this work Heiden described many new taxa, 2 genera, 92 species, 51 varieties, and 20 formae (the numbers given by Kolbe in Heiden & Kolbe 1928, p. 676, are all incorrect). Of these taxa we were unable to locate with sufficient certainty 9 species, 9 varieties, and 4 formae. Considering the comparatively small number of slides left, I feel that our gleaning has been relatively successful and deserves publication, also under the aspect that many of Heiden's taxa were never again observed after Heiden, e.g. the somewhat enigmatic genus Vanhoeffenus."
Heinrich Heiden and his last work 1
Bibliography of Heiden's publications 5
Heiden's diatom types 6