His attention having been directed by Matthias Jakob Schleiden, then professor of botany at Jena, to the microscopical study of plants, he engaged more particularly in that branch of research.

I conclude... that, unlike Remak, he did not observe nuclear division... it is clear that Nägeli did not in 1844 have any idea of the importance of the nucleus in the life of the cell.

[9] Among his other contributions to science were a series of papers in the Zeitschrift für wissenschaftliche Botanik[10] (1844–1846); Die neueren Algensysteme (1847); Gattungen einzelliger Algen (1849); Pflanzenphysiologische Untersuchungen (1855–1858), with Carl Eduard Cramer; Beiträge zur wissenschaftlichen Botanik[11] (1858–1868); a number of papers contributed to the Royal Bavarian Academy of Sciences, forming three volumes of Botanische Mitteilungen (1861–1881); and, finally, his volume, Mechanisch-physiologische Theorie der Abstammungslehre,[12] published in 1884.

We can forgive him for being ignorant, a scientist of his time who did not really have the equipment to understand the significance of what Mendel had done despite the fact that he (von Nägeli) speculated extensively about inheritance.

[15] Nägeli also coined the terms 'Meristem', 'Xylem' and 'Phloem' (all in 1858) while he and Hofmeister gave the 'Apical Cell Theory' (1846) which aimed to explain origin and functioning of the shoot apical meristem in plants.