156 SOME REACTIONS AMONG ANIMALS 



2. Note that the segments farthest from the small (head) 

 end are the largest. They contain the eggs of the worm, and 

 as they ripen the segments are set free and pass from the 

 body of the host (man). 



3. Suppose these eggs or young become scattered about 

 where cattle and hogs are feeding. What may happen ? 



4. The young are provided with hooks and are able to bore 

 through flesh. What do you think is the purpose of the 

 hooks ? 



Conclusions. 1. Suppose uncooked or underdone beef or pork 

 containing the young of these worms should be eaten by man. 

 What part of man might be infested with them ? Would man 

 be the host, or intermediate host ? 



2. What is evidently one of the best means of preventing 

 these worms from entering the human body ? 



3. Write a paragraph telling all you know of the tape- 

 worm. 



Observations. 1. Examine some encysted trichinae. (Use 

 mounted specimens or study Figures.) They may sometimes 

 be found in the flesh of the hog or other host. 



Note. As many as 120,000 to a cubic inch may sometimes 

 be found in the flesh of the pig. 



2. Suppose some underdone pork containing trichinae is 

 eaten by man, and each female worm now produces from 600 

 to 1200 young that proceed at once to bore through the walls 

 of the stomach and intestines of man to the surrounding mus- 

 cles. The man complains of cramps, rheumatic symptoms, and 

 much irritation of the muscles. He is suffering from the 

 disease known as trichinosis. 



Conclusions. 1. What precautions should be observed be- 

 fore eating pork ? 



Note. Government inspection of meats does not now surely 

 include inspection for trichinae. 



2. Eats are likely to be infested with trichinae. How may 

 cats and dogs become likewise infected ? 



3. Has an intermediate host been mentioned for the trichina? 



