Analysis of information sources in references of the Wikipedia article "Protist" in English language version.
Erste Hauptgruppe. Protozoa. Thiere, in welchen die verschiedenen Systeme der Organe nicht scharf ausgeschieden sind, und deren unregelmässige Form und einfache Organisation sich auf eine Zelle reduziren lassen.[First principal group. Protozoa. Animals, in which the different systems of organs are not sharply separated, and whose irregular form and simple organization can be reduced to one cell.]
... I here suggest a fourth or an additional kingdom, under the title of the Primigenal kingdom, ... This Primigenal kingdom would comprise all the lower creatures, or the primary organic beings, – 'Protoctista,' – from πρώτος, first, and χτιστά, created beings; ...