Haeckel on Infusoria

Abstract

IN this communication^*Prof. Haeckel discusses the different views which have been entertained as to the structure of the Infusoria, and adopts that of Prof. Siebold, that they are unicellular. This constitutes in his opinion a fundamental distinction betweent hem and the rest of the animal kingdom, although, strictly speaking, some species, as for instance, Loxodes rostrum, and Enchelys gigas, have more than one nucleus, and must, therefore, be regarded as physiologically consisting of more than one cell. Prof. Haeckel, however, does not attach much importance to these exceptional cases, because the multiplication of the nuclei involves little change of organisation in other respects.