312 BUILDINGS, SANITATION, AND DISEASES 



Thorn-headed Worm This parasite is much less common 

 than the round worm. It is usually found attached to the wall 

 of the intestines by its hooked proboscis, from which it 

 derives the name of " thorn-headed." In length it is similar 

 to the round worm, but its surface is somewhat wrinkled, and 

 the posterior extremity is blunt. Though only a few are 

 usually found in an animal, they do much more damage than 

 the round worm, irritating the lining of the intestine, and 

 sometimes causing severe inflammation. It would be difficult 

 to distinguish the symptoms from other intestinal derange- 

 ments, but a post-mortem examination would readily reveal the 

 presence of the worm. 



Pin- Worm. The pin-worm is very small and might be 

 easily overlooked in a careless post-mortem. It is usually 

 found near the beginning of the large intestine, often hidden 

 in the folds of the lining membrane. It is a very common 

 parasite of swine, and does not seem to cause much incon- 

 venience to the animal. 



Whip- Worm. This is also a small worm, being about one 

 and one-half inches long. It attaches its head to the lining 

 of the intestine, and is usually found in the beginning of the 

 large intestine. The anterior portion is very thin and hair- 

 like, and the posterior portion is thick and cylindrical in shape. 

 Like the pin-worm, it does not seem to create much disturbance, 

 but must be more or less injurious. 



Treatment for Intestinal Worms Preventive treatment 

 consists in keeping buildings and surroundings clean and 

 sanitary. Feeding in filthy yards and allowing to drink stag- 

 nant water are practices which favor the spread of parasites. 



As to medicinal treatment, the writer has found that allow- 

 ing hogs to have access to a mixture of charcoal and salt, or 

 charcoal, wood afehes, and salt, seems to be quite effective in 

 driving out round worms. 



