PATHOLOGICAL SIGNIFICANCE. 221 



I think we may therefore, in the meantime, conclude that the 

 intestinal Coccidia, which have been observed by Kjellberg^ and 

 Eimer^ even in man, constitute a species different from Coccidium 

 wnforme, characterised especially by their smaller size, their short 

 period of incubation, and their position in the epithelial cells of the 

 membrana villosa. Considering the changes in the epithelium 

 effected by this parasite, and first observed in this case, the species 

 may be not unfittingly named Coccidium perforans. 



[That the intestinal Coccidia of Mammalia belong to numerous 

 different species may be seen not only from the forms observed by 

 Eimer, but also from the discovery of Coccidium Rivoltce, Grassi, 

 which inhabits the large intestine of the cat, and, after a period of 

 cultivation in water, produces two Psorosperms, each of which yields 

 four sickle-shaped bodies.^ — E. L.] 



Pathological significance of Coccidia. 



The foregoing account shows indubitably that the changes caused 

 by the Coccidia in the bile-ducts and liver are, or may be, of fatal 

 importance. They not only exert a pathological influence by inter- 

 fering with the normal function of the liver, by obstructing the 

 secretion of bile over a more or less considerable area, by destroying 

 the tissue of the gland, and thus restricting the quantity of secretion, 

 and by deteriorating the quality of the latter by mixture with other 

 substances, but also by pressing on the blood-vessels of the liver, and 

 causing more or less intense disturbances of the circulation according 

 to the position and size of the tumour. To what degree metabolism 

 may be affected in consequence may be illustrated by the fact that, 

 according to my honoured colleague Professor Cohnheim, it is im- 

 possible to produce diabetes by the usual operation in a rabbit in- 

 fested with Coccidia. As soon as the disease has attained a con- 

 siderable development, the animals die. They become very thin after 

 being sickly for some weeks, they lose their appetite and previous 

 activity, begin to breathe quickly and violently, and finally die in 

 convulsions. 



Nor does the rabbit alone thus suffer, but even man, although he 

 is obviously not exposed in the same degree to the possibility of a 

 frequent and numerous introduction of germs, is occasionally affected ; 

 and the first case which has come within the range of observation, 



' Virchcyuis ArcMv f. pathol. Anat., Bd. xviii., p. 527, 1860. 



' Loc. cit., p. 16. 



' See Grasoi, " Intorno ad alcuni protisti endoparassitioi," Atti Snc. Ital. Nat. Sci.: 



Miiano, vol. xxiv., 1881. digitized by Microsoft® 



