In literature many other statements are found as to the occurrence of Coccidia-like organisms in different diseases of man. In some of the cases the parasites proved to be fungi. This was the case with the parasites of a severe skin disease of man, formerly called _Coccidioides immitis_ and _Coccidioides pyogenes_. Other statements are founded on misapprehensions, or are still much disputed. If reference is here made to “_Eimeria hominis_,” R. Blanchard, 1895, this is done on the authority of the investigator mentioned. The structures in question are nucleated spindle-shaped bodies of very different lengths (18 µ to 100 µ), which either occurred isolated or were enclosed in large globular or oval cysts, alone or with a larger tuberculated body (“residual body”). These formations were found by J. Künstler and A. Pitres in the pleural exudation removed from a man by tapping. The man was employed on the ships plying between Bordeaux and the Senegal River. Blanchard looks upon the fusiform bodies as merozoites and the cysts as schizonts of a Coccidium. On the other hand, Moniez declares the spindle bodies to be the ova and the supposed residual bodies to be “floating ovaries” of an Echinorhynchus. Severi’s “monocystid Gregarines,” which were taken from the lung tissue of a still-born child, are also quite problematical. No less doubtful are the bodies which Perroncito calls _Coccidium jalinum_, and which he found in severe diseases of the intestine in human beings, pigs, and guinea-pigs; Borini also reported another case. Order. *Hæmosporidia*, Danilewsky emend. Schaudinn. The Hæmosporidia are a group of blood parasites, comprising forms differing greatly among themselves. Some of the forms need much further investigation. However, there are certain true Hæmosporidia which present close affinities with the Coccidia, leading Doflein to use the term *Coccidiomorpha* for the two orders conjoined. The Hæmosporidia present the following general characteristics:-- (1) They are parasites of either red or white blood corpuscles of vertebrates during one period of their life-history. (2) They exhibit alternation of generations--asexual phases or schizogony alternating with sexual phases or sporogony--as do the Coccidia. (3) There is also an alternation of hosts in those cases which have so far been completely investigated. The schizogony occurs in the blood or internal organs of some vertebrates while the sporogony occurs in an invertebrate, such as a blood-sucking arthropod or leech. (4) Unlike the Coccidia, resistant spores in sporocysts are not generally produced, such protective phases in the life-cycle being unnecessary, as the Hæmosporidia are contained within either the vertebrate or invertebrate host during the whole of their life. The Hæmosporidia may be considered for convenience under five main types:--