26 COCCIDIOSIS. 



ing more spores, and so rapidly increasing the area of the disease. 

 It is supposed that these sporiferous cysts are carried with 

 dust, &c., and hence get taken into the mouth with food, 

 eventually reaching the liver. The sporocyst ruptures in some 

 region near the liver and the sporoblasts appear ; these latter 

 burst and discharge the spores or falciform bodies, which 

 become active, and are said to ascend by the ductus chole- 

 dochus to the epithelium of the liver and bile-duct. Here the 

 germs, having entered some of the hepatic cells, cause these cells 

 to rupture, and they may even destroy the walls of the bile-duct 

 itself. They finally encyst, pass out into the intestine, freed by 

 the breaking up of the tissues in which they are embedded, and 

 so out to ground by the anus of the diseased animal. 



Their presence causes the liver to swell. They are detected 

 by the creamy cystic areas, varying in size from a miUet-seed to 

 that of a pea. They are often so abundant that the cells of the 

 Uver atrophy, and cheesy-like masses appear not only in the 

 liver substance but in the bile. These prurigerous masses on 

 microscopic examination are found to contain numbers of coc- 

 cidia. The disease may affect man as well as the rabbit, and 

 I have found it in the liver of fowls. It may possibly be taken 

 for tuberculosis unless carefully examined. The walls of the 

 intestine may be invaded as well as the liver. 



To suchlike forms is the " diphtheritic roup '' of poultry due, 

 the " canker " of pigeons, turkeys, and fowls, and other minor 

 complaints ; whilst in man that terrible scourge malaria is also 

 caused by some amoeboid form in the blood, the germs being 

 transmitted to him by mosquitoes, as has been recently demon- 

 strated by Golgi. 



Enough has been said of this group of simple animals, the 

 most rudimentary forms of animal life that exist, to show that 

 they are of some considerable importance, not only to the 

 farmer and poultryman but to man in general, and that a 

 slight knowledge of their habits and life-histories is not only 

 of interest but of economic value to us. 



