OUR DOMESTICATED ANIMALS. 7 



size from half to rather more than one inch in length, 

 and is sometimes as much as two-thirds of an inch in 

 breadth. If any proof were wanting as to its affinity 

 with the planarians, it is only necessary to look to the 

 arrangement seen in the digestive organs. The present 

 figure, reduced from one by Blanchard, should be com- 

 pared with that of the planarian. In this illustration a 

 refers to the oral sucker, b to the bulb of the oesophagus, 



Fig. 2. Common Fluke. 



and c to the main digestive tube of one side ; the other 

 internal organs, as well as the external ventral sucker, 

 being unrepresented. 



The common fluke is found in most ruminants, includ- 

 ing antelopes and deer j and it has been described as also 

 infesting the horse, ass, hare, rabbit, kangaroo, and beaver. 

 Its alleged presence in the last two quadrupeds requires 

 confirmation ; but I can testify to its occasional presence 



