85 



The)- \ ai)' much in size, sometimes being as small as a pea, and occasionally 

 as large as a good-sized cocoa-nut. They may or may not produce 

 symptoms, which vary according to the organ invaded, and the size and 

 exact position of the cyst. This hydatid is common in man, being often 

 found in the liver, and sometimes in other organs ; and it may attain in him 

 a Aery large size. This hydatid or cyst in its early form is small and 

 j,dobular, with transparent walls and finely granular contents. In its later 

 stages, when it has much increased in size, the walls become thick, and tiie 

 contents fluid. Sometimes these c}sts contain several ]:)ints of clear fluid. 



In the above picture B shows the echinococcus of the dog, magniflcd ; 

 € is one of the little heads which are formed in the cyst wall : X is the part 

 where the head is attached to the cyst wall. 



