XVIII. Contributions to the anatomy of the central nervous system in vertebrate animals

Abstract

Among the numerous writers who have turned their attention to the nervous system of Fishes, a list of whom comprises most of the great anatomists of the present and past century, nearly all have confined their investigations to the brain of the Teleostei, to which their attention was almost exclusively directed, and only to a small extent was the nervous system of the Piagiostomata referred to. The names of these writers were given in the first of this series of papers. Busch was the first who devoted a treatise entirely to the nervous system of the Plagiostomata, with which he combined the Ganoids. Written in Latin, this is a plain and, upon the whole, accurate descrip­tion of the external or macroscopic appearance of the brain of the Plagiostomata and Ganoids. Miklucho-Maclay’s contribution, also macroscopic, appeared in 1870. In it he propounded an entirely new theory as to the arrangement of the various parts of the central nervous system. I have made some remarks on this in a former paper; suffice it here to mention that he describes as the thalamencephalon (“ Zwischenhirn ”) that part of the brain which the majority of anatomists consider to be the optic lobe, and the lobe which almost unanimously has been described as the cerebellum he maintains to be the mesencephalon, while he restricts the term hind brain to the small posterior and inferior tuberosity of the cerebellum.