Translation of the original German introduction by Ernst Haeckel:
Phylum of Vermalia (Wurmtiere); - subclass of Rotatoria (Rädertiere).
Rotatoria (Rädertiere) are Vermalia of very minor size, usually invisible to the naked eye; only few species reach a size of 1-2 mm. They dwell for the most part in freshwater, some in the sea; dried up they can poise for a long time in a state of apparent death; only in contact with water they revive. Possession of a peculiar ‘wheel organ’, a flexible disc at the head end of a ovoid or scutiform body, determines the name of these Vermalia; the vivid movement of the tender cilia that occupy the rim of this loped disc in one or several rows bring about a water whirl that is used for swimming as well as sweeping food; thus many Rotatoria create the impression of a pair of rotating wheels, especially in case the disc is clearly double-loped. Most Rotatoria swim freely in water; some crawl (like caterpillars) by bending, stretching and pulling in a segmented appendix of the back end of the body, the so-called ‘foot’ (fig. 6, 7, 8). With the help of two claws or tale lopes at the end of which they can temporarily attach themselves [German sentence incomplete]. In the centre of the transparent body one can see the intestinal canal consisting of three sections: a ‘pharynx head’ in front with a pair of flexible, chewing teeth, in the middle a rounded stomach with a pair of lateral liver glands (Fig. 3, 8); at the back the straight intestine at the both sides of which are located the branches of the horseshoe-shaped ovary (fig. 3, 4). In the right and left laterals of the body a pair of vermiculated canals can be made out flowing out at the back, the excretion organs or kidneys (Nephridiae, fig. 5-8). The solid shell covering the body of many Rotatoria consists of Chitin and is frequently ornamented with ribs and spikes (fig. 7, 8).
Translation by VR Translators Bangalore
We've scanned the original lithography at 1200dpi on the Epson A3 scanner of A3 scanner huren. You can download a 400dpi JPEG here.