208 STUDIES IN INSECT LIFE, ETC. 

 alimentary tract, especially the caeca, which be- 

 come swollen and inflamed. After a time some 

 of them produce small forms (males), and others 

 change into large forms (females) ; these two 

 forms fuse, and the resulting stage is the cyst 

 mentioned above, which, passing from the body, 

 infects the whole moor. There are many details 

 omitted in this short abstract of the complicated 

 life-history of this parasite, which have been 

 worked out in the grouse by Dr. Fantham at 

 Cambridge ; but enough has been said to show 

 the nature of the disease, which is well known 

 to occur in several other animals. There is a 

 Coccidiosis of the rabbit, and a very fatal form 

 attacks pigeons, fowls, and pheasants, and the 

 grouse Coccidium if administered to chickens will 

 set up the disease in fowls. 



To repeat a little, for the life-history of this 

 parasite is very complicated : 



The chief source of contamination on the 

 moors is the droppings of other diseased grouse. 

 The droppings contain thousands of cysts (oocysts) 

 or spores of the parasite, and these spores, with 

 their hard coats, are extremely resistant, and 

 can endure for very long periods without the 

 death of their contents, which gradually divide 



