WORMS. 317 



its attack should so long- have escaped the observation of 

 naturalists. It is not, I believe, very hurtful, nor is it very 

 common in dogs. 



Of those worms which live and breed within the dog-, and 

 may be considered indig-enous to him, the Tcenia, or tape- 

 worm, is the most prejudicial, and the most difficult to re- 

 move *. I have known four or five hundred joints (each a 

 distinct animal) passed by a dog-, whose united leng-th would 

 encircle his body many times. Sometimes they become 

 coiled up into a ball, which thus forms an impenetrable ob- 

 struction within the intestines, and destroys the dog-. 



The Teres, or long- cylindrical worms, resembling- earth- 

 worms in fig-ure, but of a whitish colour, are the most common 

 to dog-s, and, when existing- in great numbers, particularly in 

 puppies and young dogs, often prove fatal by the convulsions 

 they occasion. Their natural situation is within the intestines, 

 but they sometimes crawl from them into the stomach, and 

 are then brought up by the sickness they occasion. 



The Ascarides, or small thread-worms, likewise occasi- 

 onally infest dogs, residing principally within the rectum. 

 They produce an intolerable itching in the parts behind, to 

 relieve which, dogs troubled with them are seen continually 

 drawing the fundament along the ground. Except by the 

 irritation occasioned, which, when excessive, may weaken, 

 they do not appear to do much internal injury. 



The constitution of some dogs appears particularly favour- 

 able to the generation of worms ; for, destroy them as often 

 as you will, they soon return again. Puppies, during every 

 stage of their growth, are very liable to them. In many, 

 the increase of the body appears checked by their ravages. 

 The presence of worms, when they exist in considerable 

 numbers, is easily detected ; for such a dog has usually a 



* It is remarkable how universal is the attack of this parasitic ani- 

 mal: when roach and dace are observed to swim near the surface of the 

 water exhausted, and incapable of descending long together, if they 

 become the subject of examination, they will be found, in most instances, 



affected with this singular worm. 



