Nothing shows better the earnestness of Bauhin’s research than the fact, that he devoted the labour of forty years to his ‘Pinax,’ in order to show how each one of the species given by him was named by earlier botanists. The example already given from Fuchs shows how many names a plant had received by the middle of the 16th century; even in Dioscorides and Pliny we find a whole row of names given for a single plant, and the botanists of Fuchs’ time used their utmost endeavours to attach the names in Dioscorides and other ancient writers to particular plants found in central Europe. Dioscorides, Theophrastus, and Pliny either add no descriptions to the names of their plants, or they describe them in so unsatisfactory a manner, that it was a very difficult task for the science of that day, as it is still for us, to recognise the plants of the ancient writers; hence arose such a confusion of names that the reader of a botanical work can never be sure whether the plant of one author is the same as that of another with the same name. A description of a plant is therefore usually accompanied in the 16th century by a critical enquiry how far the name used agrees with that of other authors. Kaspar Bauhin sought to put an end to this condition of uncertainty by his ‘Pinax,’ in which he showed in the case of all species known to him what were the names given to them by the earlier writers, and he has thus enabled us to see our way through the nomenclature of the period of which we are speaking; the ‘Pinax’ is in a word the first and for that time a completely exhaustive book of synonyms, and is still indispensable for the history of individual species—no small praise to be given to a work that is more than 250 years old. It would not have been unsuitable to the purpose of the author of the ‘Pinax,’ if he had allowed himself to give the plants in alphabetical order, but instead of this we find a careful arrangement according to natural affinities. This directly proves what is also confirmed by the ‘Prodromus,’ that Bauhin regarded such an arrangement as of the greatest importance. In this point, as in others, he goes far beyond his predecessors; he pursues the same method as de l’Obel had pursued forty years before, but he carries it out more thoroughly. At the same time he shares with his predecessors the peculiarity of not distinguishing the larger groups, which with some exceptions answer to our present families, by special names or by descriptions; it is only from the order in which the species follow one another that we can gather his views on natural relationship. It follows therefore that the natural families, so far as they are distinguishable in Bauhin’s works, have no sharp bounding lines; we might almost conclude that he purposely avoided assigning such limits, that he might be able to pass without interruption from one chain of relationship to another.