THE TAPEWORM LARVAE 



199 



som relative to this method, Federal meat inspection regulations provide 

 that beef carcasses showing a slight degree of infestation may be passed 

 for food if held for six days at a temperature not exceeding 15° F. 

 (-9.44° C), as an alternative to the requirement of retention for twenty- 

 one days. 



Symptoms. — Symptoms in bovine measles are practically nil. There 

 is rarely a history of disturbance from the presence of the cysts, and it is 

 extremely exceptional for the condition to be recognized before the 

 animal is slaughtered. 



Measles of the Pig 



Taenia solium. — Tseniidse (p. 170). This species, to which Cysticercus 

 celluloscB gives rise, also hves in the himian intestine and is commonly 

 referred to as the pork or armed tapeworm. It is smaller than T. sag- 

 inata. The head (Fig. 109, A) is globular and less than 1 mm. in diam- 



FiG. 109. — "Head" of Taenia solium (A), of T. saginata (B), and Diphyl- 

 lobothrium latum (C) . (After Boas, by Kirkaldy and Pollard) . 



eter; the rostellum is short and provided with a double crown of hooks. 

 The neck is loiig and slender. The first segments are very short, grad- 

 ually increasing in length and breadth. At about one meter (39 inches) 

 from the head they are as long as broad and have the generative organs 

 fully developed. Toward the distal end of the chain they measure 10- 

 12 mm. (3/8-1/2 an inch) in length and 5-6 mm. (1/4 of an inch) in 

 breadth. The total number of segments is from 800 to 900. The genital 

 pores are more regularly alternate than in T. saginata. The median trunk 

 of the gravid uterus has 7 to 12 tree-like lateral branches on each side. 



