Under the name _Balantidium giganteum_ n. sp., P. Krause described an Infusorian which was repeatedly observed with _Trichomonas intestinalis_ in the alkaline evacuations of a typhoid patient in Breslau. The body is ovoid, narrower and rounded anteriorly and broader and stunted posteriorly. The peristome lies to one side; the macronucleus is bean-shaped, the micronucleus small and globular; one or two vacuoles are present. The anus is at the farther end. The organism is 90 µ to 400 µ long, 60 µ to 150 µ broad (fig. 117). After a prolonged stay outside the body, it becomes rounded and encystment occurs. In the thermostat the Infusoria remain alive at 37° C. for five weeks. The species, however, hardly belongs to _Balantidium_, but to all appearances is a _Nyctotherus_ and is distinguished from _N. faba_ by the difference in size. [*Nyctotherus*] *africanus*, Castellani, 1905. In the fæces of a native of Uganda who suffered from sleeping sickness and diarrhœa and had in his intestine _Ascaris lumbricoides_, _Trichocephalus trichiurus_ and _Ancylostoma duodenale_, Castellani found a curiously shaped Infusorian, 40 µ to 50 µ long, and 35 µ to 40 µ broad, with spherical macro- and micronucleus and a contractile vacuole (fig. 118). He included the organism in the genus _Nyctotherus_, perhaps wrongly, or the parasite may have been deformed. After the patient’s death the same parasite was found in the intestine and especially in the cæcum. [Illustration: FIG. 117.--_Nyctotherus giganteus._ (After Krause.)] [Illustration: FIG. 118.--_Nyctotherus africanus._ (After Castellani.)] G. Lindner, in Cassel, studied certain peritrichal Infusoria (stalkless Vorticella), and connected them, probably incorrectly, with the most varied diseases of man and domestic animals, even with Sarcosporidia of pigs. It may be mentioned that according to a communication by letter from Schaudinn, Vorticella may be found in freshly evacuated fæces, but always only after the administration of a water enema. In spite of this, several other investigators mention Vorticellæ as intestinal parasites of man. The _Chilodon dentatus_ (Ehrenberg) recorded in 1903 by J. Guiart as a parasite of man, which may be found in all infusions, can hardly have lived in the man from whose fæces it was cultivated, but may represent a chance admixture both in the fæces and the cultivations. _C. uncinatus_ was also found as a chance parasite of man by Manson and Sambon. According to Doflein[250] (1911) certain Chilodon-like organisms have been found by Selenew in prostate secretions in gonorrhœa. Other species of the genus _Chilodon_ are known, but only as ectoparasites (_e.g._, _Chilodon cyprini_, Moroff, 1902, from the skin and gills of diseased carp). [250] _Lehrbuch der Protozoenkunde_, 3rd ed., p. 963.