Personal names (eponyms) of real or fictitious people can be found both in botanical and zoological nomenclature ever since Linnaeus's reform efforts (and earlier too) – yet they were never uncontroversial. The same applies for scientific chemical nomenclature where the situation is more complex because besides systematic names, semi-systematic, and even non-scientific (trivial) names such as Glauber's salt or ammonia (both derived from eponyms), are officially accepted. One of the semi-systematic names is kaempferol, the designation of a natural dyestuff (flavonoid) that occurs in numerous plants, among them Kaempferia galanga. The course of the discovery and name-giving process for this organic compound is traced, elucidating that not only Engelbert Kaempfer was involved, but a whole series of natural scientists.

In the history of zoology the English anatomist Morrison Watson (1845-1885) is considered to be the discoverer of the masculinized sexual organs of the spotted hyena.

Philipp Franz von Siebold (1796–1866) was one of the earliest European naturalists to live in Japan. Through most of the nineteenth century, however, until the 1860s, movement of foreigners within Japan was severely restricted, impairing Siebold's ability to observe wildlife in the countryside or collect zoological specimens. Among the Japanese mammals that Siebold was able to see, if not necessarily in the wild, and acquire examples of, was Pteropus dasymallus, the Ryukyu Flying Fox. On the basis of Siebold's early work, Coenraad Jacob Temminck (1778–1858), in 1825, first described the species scientifically. Siebold's initial observations on the fruit bat's range, however, proved to be incorrect. His notes on the species' distribution in and around Nagasaki in southern Kyushu and Tokyo in central Honshu were particularly contradictory, apparently based, at least in part, upon an initial confusion with either Pteromys petaurista (Japanese Giant Flying Squirrel) or Pteromys momonga (Japanese Dwarf Flying Squirrel).

In the history of botany, Adam Zalužanský (d. 1613), a Bohemian physician, apothecary, botanist and professor at the University of Prague, is a little-known personality. Linnaeus's first biographers, for example, only knew Zalužanský from hearsay and suspected he was a native of Poland. This ignorance still pervades botanical history. Zalužanský is mentioned only peripherally or not at all. As late as the nineteenth century, a researcher would be unaware that Zalužanský’s main work Methodi herbariae libri tres actually existed in two editions from two different publishers (1592, Prague; 1604, Frankfurt). This paper introduces the life and work of Zalužanský. Special attention is paid to the chapter “De sexu plantarum” of Zalužanský’s Methodus, in which, more than one hundred years before the well-known De sexu plantarum epistola of R. J. Camerarius, the sexuality of plants is suggested. Additionally, for the first time, an English translation of Zalužanský’s chapter on plant sexuality is provided.

The Swiss physician and naturalist Conrad Gessner (1516–1565) is known as the author of Historia animalium, a multi-volume encyclopaedia published between 1551 and 1558 and intended as an up-to-date version of the Aristotelian work of the same title. It included little-known animals from the New World and other regions outside Europe. To realize this ambitious project, Gessner was dependent on a great number of supporters and informants. One of them was the English physician John Caius (1510–1573), who shared with Gessner a special interest in the medical works of Galen. This common interest resulted in a meeting between the two scholars, leading to cooperation and a life-long friendship. The fact that Caius and Gessner were on good terms and cooperated for Historia animalium, as well as for Gessner's unfinished “Historia plantarum”, has often been noted, usually however in a rather cursory manner. This article provides an analysis of how and when Caius's information found its way into Gessner's works.