254 THE PROTOZOA 



results, and we get the nucleus and the protoplasm both stained, but the 

 former more deeply. Sections stain with cosine and hsematoxylin as well 

 as methylene blue. 



PARAM^ICIUM COLL 



Found in the intestines of man and swine. 



Microscopical Appearances. Elliptical infusoria, their whole 

 surface being covered with cilia. In man they are 60 to 70 /u long, and 

 in swine 70 to 100 /x long. The mouth is funnel-shaped, the nucleus 

 bean-shaped, and they possess two contractile vacuoles. They multiply 

 by dividing into four and by conjugation, also sometimes becoming 

 encysted. 



COCCIDIA. 



The best known coccidia are those found in the rabbit and the fowl, 

 and, according to Rieck, there are two different varieties a liver and a 

 bowel species, the former causing peculiar white or abscess-like cavities 

 in the liver (due to local dilatation of the bile-ducts), the other inhabiting 

 the intestines and causing a most acute and fatal inflammation. 

 M'Fadyean records an outbreak amongst pheasants of the intestinal 

 variety, where the coccidia penetrated the glands of Lieberkiihn and 

 invaded their epithelium. The same author also mentions an outbreak 

 amongst lambs. 



Zschokke, Hess, and Guillebeau mention a form of dysentery 

 amongst cattle in Switzerland, produced by coccidia, and known as f red 

 dysentery ' and ' dysenteria haemorrhagica coccidiosa.' It has also been 

 produced experimentally in cattle with sporulating coccidia. 



The coccidia are unicellular animal parasites belonging to the class 

 Sporozoa. In the adult state they are ovoid in shape and enclosed in a 

 double-contoured shell or cyst, flattened at one of its poles, 30 to 50 n 

 long and 14 to 28 /x broad. The protoplasmic contents of the encysted 

 forms separate from the wall and contract into a ball-shaped mass. 



COCCIDIUM OVIFORME. 



This parasite is found in the rabbit's liver, and sometimes in the 

 intestinal canal. It enters the gall-ducts by way of the ductu, 

 choleduchus, thence into the epithelial cells, and, increasing in size, 

 becomes encysted. It is surrounded by a slender external membrane 

 and a shining double inner membrane. The permanent cysts have 

 granular contents and a nucleus. The development does not proceed 



