OUR DOMESTICATED ANIMALS. 



55 



single title. We cannot now abandon the general term ; 

 yet, when not addressing the helminthologist, it is 

 desirable to offer some distinctive prefix, in order to 

 characterise the particular hydatid referred to. The first 

 of the three bladder worms in question is the common 

 hydatid. This parasite is almost as abundant iu cattle as 

 in sheep, and it has been described by naturalists under 



Fig. 13. Hydatids Encysted within the Lungs and Liver. 



upwards of twenty different names. It is best known to 

 us as the Echinococcus veterinorum. It infests mankind, 

 monkeys, equine animals, and all ruminants. Specimens 

 have also, it is said, been obtained from felines and 

 rodents, and the distinguished zoologist Yon Siebold also 

 described an example taken from the lungs of a turkey. 

 The annexed and much-reduced illustration (Fig. 13), 

 which unfortunately fails to do justice to the original 



