252 PARASITIC DISEASES 



coming to rest, it develops into the larva or bladder- worm, which 

 when eaten by a proper host gives rise to the matnre tapeworm. 

 The following tables give the most important tapeworms : 

 Adult Forms 



Name Host Organ 



Taenia expansa Sheep and ox Intestine 



Tajnia finibriata Sheep Liver 



Ta>nia denticulata Cattle Intestine 



Taenia alba Cattle Intestine 



Taenia perfoliata Solipeds ■ Intestine 



Ta»nai mamillana Solipeds Intestine 



Taenia echinococcus Dog intestine 



Larval Forms 



Name Host 



Cysticercus bovis Cattle 



Cysticercus cellulosa Swine and man 



Cysticercus tennicoUis Cattle, sheep and swine 



Coenurus cerebralis Cattle and sheep 



Echinococcus polymorphus C attle, sheep, swine and man 



The adnlt tapeworms Tamice saghiata and solemn, of which 

 the Cysticerci bovis and cellulosa are the larva? forms, occur in 

 man. The larva* are present in meat and pork, and this form of 

 parasitism is termed beef measles in cattle and pork measles in 

 hogs. Man becomes host for these two forms of tapeworms 

 through eating measly pork or beef that is not properly cooked. 



The dog is the host for Tcenice marginaia, coenurus and 

 echinococcus. The larva* forms of these toeniw are the Cysti- 

 cercus tennicoUis, Coenurus cerehralis and Echinococcus poly- 

 morphus. C. tennicoUis is a parasite of the serous or lining mem- 

 branes of the body cavities. It is not of great economic importance. 

 C. cerehralis is a parasite of the brain of sheep, and may cause a 

 heavy death rate in flocks that are infested with it. E. polymor- 

 phus is a parasite of the liver, but it may occur in other organs. 



The Thorn-headed Worm or Acanthocephale, — This para- 

 sit© requires a secondary host. In this case a particular species 

 of the May-beetle larva or white grub that is commonly found 

 about manure piles and in clover pastures is the host. The 

 hog eats a white grub that is host for the larval form. The 



