On The Curious Illustration of The Foraminifer Peneroplis Planatus In Haeckel'S Kunstformen Der Natur (1899–1904)

Abstract

In Ernst Haeckel’s classic book Kunstsformen der Natur (Art Forms in Nature), forams are prominent; they occupy three of the 100 plates. In one plate, the centerpiece is Peneroplis planatus, shown with extended rhizopods, and organisms from the plankton. It is a very curious illustration as it is the only foram shown living and one of only two organisms in all of Kunstsformen der Natur pictured with possible prey. Here I show that the apparent planktonic prey of P. planatus closely resemble the prey items shown in Haeckel's earlier illustrations of his supposedly primitive life forms Protogenes primordialis and Protomyxa aurantiaca in the 1860s. These forms, now considered dubious, were described as possibly naked forams by Claus (1872), a diagnosis repeated by Brady (1884) in his HMS Challenger report, a source of many illustrations in Haeckel's foram plates. I speculate that Haeckel's depiction of P. planatus, shown much like his primitive forms, was a discrete nod of agreement with the diagnoses of Claus (1872). Examples of Haeckel's stylizations of the morphology of forams in his plates are also shown in support of the notion that Haeckel exercised artistic liberty in his depictions of forams.