136 INFECTIOUS AND PARASITIC DISEASES. 



T^NIA Sagi 

 NATA (T. me- 



The unarmed or beef tape-worm is the com- 

 monest of tape-worms found in America, 

 diocanellata) ^^ inhabits the small intestines. In length 

 it varies between 9 and 24 feet. The head, 

 which measures about 2 millimeters 

 in breadth, is pyriform and with- 

 out booklets, but contains four 

 cup-shaped suckers on its ventral 

 aspect. The ripe segments are 

 from 17-18 milhmeters in length 

 by 8-10 millimeters in breadth. 

 Cattle act as intermediate hosts, 

 and eating uncooked beef contain-, 

 ing the cysticerci gives rise to in- 

 festment in man. 



Both eggs and proglottides are 

 passed in the stools. The proglot- 

 tides are easily recognized and are 

 diagnostic of an adult worm. 

 Symptoms due to tape-worms may 

 be absent entirely, or may consist 

 of occasional colic and an abnormal 

 appetite. 

 Or pork tape-worm is a rare parasite in 

 the United States. In Europe it is not 

 uncommon. It is a smaller cestode than 

 tcenia saginata; the head measures less than 

 the head of a pin (0.6-1 millimeter) ; the ripe proglottides 



Fig. 14. — TcBnia medi- 

 ocanellata. (Gould, after 

 Leuckart.) 



T^NIA 



Solium. 



