66 WORM PARASITES. 



some considerable time. Should some carnivorous 

 animal eat these cysts, supposing it to be a fitting 

 < host/ the walls of the cyst are broken down, and 

 the scolex or scolices set free. When once free from 

 the cyst, they anchor themselves on to the intestinal 

 mucous membrane, and by budding from the neck 

 produce the ribbon-like sexual tapeworm from which 



we started. 



Thus we have two distinct types of life in the cycle 

 of a tapeworm's existence — one the sexual tapeworm, 

 living in the intestines of animals only, and, secondly, 

 the cyst that produces one or more tapeworm heads 

 by budding, that is asexually, and living in the 

 various organs and connective tissue of another 



host. 



By the knowledge of the life-history of these Platy- 

 helminths we are enabled to check their increase. 

 Take, for example, the well-known disease of 'measles' 

 in pork, the cystic stage of Tcenia solium, the Human 

 tapeworm ; and, again, the cyst Camurus cerebralis, 

 causing 4 Staggers ' or ' Sturdy ' in Sheep, and its 

 tapeworm form Tcenia camurus that lives in the 

 Dog. By not eating ' measly pork' and by not 

 alio win o- dogs or other canines to get the brain with 

 the cyst of C. cerebralis, we can stop the presence of 

 the obnoxious human pest, and stop the furtherance 

 of the ' Gid ' in our flocks. Unfortunately the com- 

 plete life-histories of many Cestodes are unknown, 

 and this, we are sorry to record, is especially the 

 case in those that attack our Poultry. Twelve species 



