Author: FREUD, S.,
Title: Über Spinalganglien und Rückenmark des Petromyzon.
Description: (Wien, K.k. Hof- und Staatsdruckerei, 1878. ). W. 4 lith. pls. by F.Schima after Freud. Original brown printed wrappers. (44 lvs.: 87, I pp.). (Offprinted from "Sitzb. der. k. Akad. der Wiss., 3 Abth., vol. 78 (1878). First separate printing. DSB V, pp. 171 - 181: Jones, Life and Work, vol. I, pp. 51 - 53: 'Freud continued in his thorough investigation of the Reissner cells, and published a second report on Petromyzon in July of the following year (1878). Here he assembled an amazingly complete bibliography - 18 pages of his report deal with the literature. ...aided by an improvement in the technique of the preparation, Freud established definitely that the Reissner cells "are nothing else than spinal ganglion cells in which, on those low vertebrates, where the migration of the embryonic neural tube to the periphery is not yet completed, remain within the spinal cord. ...". This solution of the problem of the Reissner cells was a triumph of precise and genetic interpretation - one of the thousands of such small achievements which have finally established among scientists the conviction of the evolutionary unity of all organisms.': Norman Coll. vol. II, F3: Norman Sale III, 1345: Grinstein, 10383: Grinstein Freud bibl. 1878a, item 34: Stanford, Freud exh. (1991), item 3: 'Freud's third paper published as a medical student continued his research on the large Reissner cells in the spinal cord of the fish Petromyzon, ...': Freud was aided in his research by his improved methods of tissue preparation: "By the use of gold maceration technique it was possible to make a complete survey of the spinal ganglia of Petromyzon" (Abstracts of the scientific writings, p. 229). The information in his previous paper, as he discovered, had already been set forth in 1863 by the Russian biologist Kutschin, but Freud made a major contribution to evolutionary biology by showing that the spinal ganglion cells of Petromyzon, which "exhibit every transition between bipolarity and unipolarity" (...), represent a transition between the bipolar cells of lower and unipolar cells of higher vertebrates. Freud must have been pleased with this piece of research as he referred to it many years later in his Introductory lectures.': Gray, P., Freud, p. 36: 'Some of Freud's earliest published papers, written between 1877 and 1883, detail findings that are far from trivial. They substantiate evolutionary processes revealed in the nervous structures of the fish he was examining under his microscope. What is more, it becomes clear in retrospect that these papers form the first link in the chain of ideas leading to the draft of a scientific psychology he would attempt in 1895.': Freud's very rare third papaper, published as a medical student, aged 22.

Keywords: system fishes neurology comparative anatomy nerve Brk