WORMS. 475 



WORMS. 



Worms are a fertile source of disease in the dog, destroying 

 every year more puppies than distemper itself ; and, in spite of 

 every precaution, appearing in the kennelled hound or shooting- 

 dog, as well as the pampered house-pet and the half-starved cur. 

 In old and constantly used kennels they are particularly rife, and 

 I believe that, in some "way, their ova remain from year to year, 

 attached either to the walls or to the benches. All of the varieties 

 met with are propagated by ova, though some, as the Ascaris lum- 

 bricoides, are also viviparous, so that the destruction of the worms 

 actually existing at the time the vermifuge is given does not neces- 

 sarily imply the after clearance of the animal, who may be infested 

 with-them as badly as before, from the hatching of the eggs left" 

 behind. The natural history of these parasites is, however, very 

 imperfectly understood, in spite of the carefully recorded and ex- 

 tended labours of Eudolphi, Schmalz, Cloquet, Creplin, aud our 

 own Owen ; indeed, as it is not till after the death of the animal 

 infested by them that they can be reached, it is only wonderful 

 that so much is known. Besides the intestinal worms, there are 

 also others met with in the dog, including the large kidney worm, 

 (Strongylus gigas), which shall presently be described, and the 

 hydatid, which is in all probability the cause of turnside ; but, 

 though found in the dog's brain, its presence has not, I believe, 

 been clearly associated with that disease. I shall, therefore, first 

 describe the appearance of each kind of worm ; then the symptoms 

 of worms in general ; and, lastly, the best means for their expul- 

 sion. 



The Maw-worm in the dog is about an inch in length {fig. i), 

 of a milky white colour, with one end cut off obtusely and slightly 



