54 



VARIOUS FORMS OF TAPEWOEMS. 



produce hundreds of scolices, future tapeworms, should a dog 

 devour the organs suffering from this echinococcosis. 



Lastly, there is a form of Echinococcus known as a multi- 

 locular form, in which the vesicles remain very small, whereas in 



the others they may assume 

 an immense size. These 

 vesicles remain attached 

 together, and may produce 

 a huge mass eight or nine 

 inches across, united to- 

 gether by . connective tis- 

 sue. These are called col- 

 loid cancers, hut Virchow 

 showed some time ago their 

 true formation. 



The secondary internal 

 vesicular formation is 

 chiefly found in man, the 

 pig, and the horse, where 

 huge hydatids are pro- 

 duced. Secondary exter- 

 nal vesicles are more gen- 

 eral in ruminants, but they 

 also occur in the pig and 

 in man. This disease is 

 found wherever dogs exist. 

 One-sixth of the popula- 

 tion in Iceland have suf- 

 ered from this plague.-' 

 It is also abundant in 

 Australia,^ India, and else- 

 It is by no means uncommon in Great Britain. 



Pia. 16. 



-TAENIA SEBBATA (nat. size), 

 Far. Dis. Ani., Neumann.) 



(From 



where. 



' Dobell, Report on Iceland. (1879.) 



^ Thomas, Hydatid Disease iu Australia. Adelaide (1884).. 



