1 ()() Coccidia parasitic in man 
latter view, which is that of some of the modern French writers. The former, 
which regards all the coccidia in the rabbit as belonging to one and the same 
species, is, however, that which has gained general currency in England and 
Germany. 
The parasites of the liver and the gut both unquestionably belong to the 
genus Eimeria Aime Schneider (1875). The correct name of the former is 
Eimeria stiedae Lindemann (1865) 1 , as was pointed out by Stiles (1902) and 
Lube (1902); but it has been given several other names, of which the most 
important are Psorospermium cuniculi Rivolta (1878), and Coccidium oviforme 
Leuckart (1879). In all but the most modern works it appears under the names 
Coccidium cuniculi or C. oviforme. 
The correct name of the coccidium of the rabbit’s small intestine—assuming 
it to be a separate species—is Eimeria perforans Leuckart (1879). Those who 
regard the two forms as identical apply the name—whatever it may be—which 
they give to the hepatic form, to the intestinal form also, as the former was 
named before the latter. In many modern works, therefore, E. perforans 
appears as a synonym under E. stiedae. In the older writers it figures either 
independently as Coccidium perforans or as merely the intestinal form of 
“C. oviforme ” or il C. cuniculi .” 
The intestinal coccidia of carnivores. The coccidia living in the intestinal 
villi of cats, dogs, and other carnivores, have also a somewhat chequered 
history. They were first seen in the dog by Finck (1854), who regarded them 
as metabolic products. Later workers—Virchow, Rivolta, Grassi, and others 
—recognized their parasitic character, and showed that they occur in the cat 
also 2 . The chief features in their development have been made out by Grassi 
(1879 a ), Railliet and Luoet (1890, 1891), Stiles (1891, 1892), and more recently 
by Swellengrebel (1914). 
Rivolta called the parasites “oviform cells” or “ Cytospermia" of the villi 
of the dog and cat 3 . They were subsequently named Coccidium Rivolta by 
Grassi (1879 a) and Coccidium higeminum by Stiles (1891). They certainly do 
not belong to the genus Coccidium (Leuckart, 1879), which is a synonym of 
Eimeria (Aime Schneider, 1875); and as they are characterized by possessing 
an oocyst containing two tetrazoic spores, they are now generally referred to 
Schneider’s genus Isospora, and known as Isospora higemina Stiles. It has not 
been determined with certainty whether the forms inhabiting different hosts 
belong really to the same or to different species. Most authors, how r ever, follow 
Railliet and Lucet (1891) in considering the parasites occurring in different 
1 Lindemann, it may be noted, called the organism Monocystis stiedae, and regarded it as a 
gregarine. 
2 In both these hosts they are far from uncommon. Similar—possibly identical—forms have 
also been described in the pole-cat ( Mustela putorius L.) and wild species of dog. 
3 “Cellule oviformi dei villi del cane e del gatto” (Rivolta, 1874, 1877, 1877 a); “ Cytospermiuvn 
villorum intestinalium canis ” (Rivolta, 1878). 
