CH. IX] INTERNAL PARASITES OF DOMESTIC ANIMALS 303 



symptoms of their presence are general weakness, anaemia, 

 diarrhoea, enlarged liver, and " pot-bellied " appearance. In 

 two or three months the victims waste away and die. The 

 post-mortem appearance of the liver exhibits a number of 

 white specks and blotches varying from the size of a pin's 

 head to that of a hazel-nut. These nodules contain masses 

 of encysted Coccidia. The surrounding lobules of the liver 

 are frequently more or less atrophied. A stage of the 

 life-history of the parasite is passed in damp earth, or 

 water or other suitably moist medium to which access is 

 gained via the droppings of its host. It is therefore 

 important to isolate, or destroy, infected individuals, to 

 burn their litter, and otherwise cleanse and disinfect their 

 hutches, troughs, etc. Dry food, clean drinking-water and 

 general cleanliness in the surroundings are the best pre- 

 cautions against the disease among domesticated rabbits. 

 Guinea-pigs are known to suffer from the same complaint, 

 which has also been recorded in man himself. In this case 

 it is probably contracted by drinking dirty or unfiltered 

 water or by eating raw green food, salads, etc., which have 

 not been properly washed. 



Trematoda. 



The Trematodes are Flat- worms devoid of external 

 cilia, being invested by hard cuticle. They adhere to their 

 hosts by means of suckers. The mouth is anterior, and 

 leads into a muscular pharynx, which by alternate contrac- 

 tion and expansion pumps the juices of the host into the 

 alimentary canal of the worm. The alimentary canal itself 

 forks into two main branches, right and left, and these 



