PARASITOLOGY. 191 



Animals hifested. — The adult infests the dog ; the 

 larva infests the rabbit. 



Parts Infested. — The adult worm is found in the 

 small intestines of the dog ; the larva or cystic form 

 is found in the peritoneal cavity of the rabbit. 



Symptoms. — The adult form in the intestines of the 

 dog produces the same symptoms and is amenable 

 to the same treatment as the preceding species ; tke 

 cysticercus pisiformis as a rule do not cause serious 

 results in rabbits. 



Taenia Serialis. 



Distribution. — Not common; reported more 

 common in European countries. 



Description. — The head is wider than the neck and 

 is provided with four sucker discs and a rostellum of 

 from twenty-six to thirty booklets ; the neck is long 

 and slender ; the segments, at first shorter than broad, 

 farther down the strobilus are as long as broad ; 

 finally the ripe segments are about two and one-half 

 times as long as broad ; these latter segments are 

 narrower at the ends than at the middle. The 

 genital pores irregularly alternate. 



Life Cycle. — The intermediate host is the rabbit and 

 rodent, which become infested through water or food 

 contaminated with the ova from the dog; in the 

 stomach the six-hooked embryos are liberated; they 

 migrate to the connective tissue and develop small 

 cysts which contain the larvae suspended from the 

 mother membrane by means of pedicles, which floats 

 in a colorless fluid. Dogs become infested by devour- 

 ing the carcasses of rabbits or rodents harboring the 

 cystic form ; the larval or cystic form is called the 



