TCENIA SOLIUM 



333 



of the pig is an elliptical vesicle with a longitudinal diameter of 

 6 to 20 mm., and a transverse diameter of 5 to 10 mm. 



Even with the naked eye a white spot may be observed in the 

 centre of the long equator, this being the invaginated head ; it is easy 

 to make it project by pressing on the vesicle (after tearing off with the 

 finger-nail the investing connective tissue), and on examining it under 

 the microscope one can convince oneself that it corresponds with the 

 head of Tcenia soliuin. 



Numerous experiments have proved that the Cysticercus cellulose 

 of the pig, if introduced into the intestine of man, grows to a Tcenia 

 solium (Ktichenmeister, 1855; Humbert, 1856; Leuckart, 1856; Hollen- 

 bach, 1859 ; Heller, 1876) ; the cysticercus has frequently also been 



FIG. 237. Large and small hooks of Tcenia solium. 280/1. 

 (After Leuckart.) 



FlG. 238. Tania solium. 21, Egg with external mem- 

 brane ; 22, without (embryophore). (After Leuckart.) 



FIG. 239. Two 

 mature proglottids 

 of Tcenia solium with 

 fully develope'd 

 uteru*. 2/1. 



cultivated purposely by feeding pigs with mature proglottids of 

 T. solium (P. J. van Beneden, 1853 ; Haubner and Kuchenmeister, 

 1855 ; Leuckart, 1856 ; Mosler, 1865 ; Gerlach, 1870 ; etc.), but success 

 did not attend the efforts to make Cysticercus cellulose? establish them- 

 selves in the intestines of pigs, dogs, guinea-pigs, rabbits and monkeys 

 (Macacus cynotuolgus), and so become adult Taeniae ; the attempts, also, 

 to infect dogs with cysticerci by means of ova were likewise, as a 

 rule, abortive. 1 



' According to Gerlach only young pigs (up to 6 months old) are capable of infection, and 

 perhaps the failure may have been due to the animals chosen for experiment being of the 

 wrong age. 



