356 THE DOG IN DISEASE. 



Thread-worms are easily destroyed by injecting into the 

 rectum salt and water, vinegar and water, an infusion of 

 quassia, etc., and retaining it there for a few minutes by 

 holding the hand covered with a cloth against the anus. 



It is highly important, to prevent the spread of worms, 

 that all the excreta after dosing, even when no worms 

 are seen, should be collected and buried deep, or, better, 

 hurned. When worms of any kind are obtained, the treat- 

 ment should be repeated, but not till the dog has recovered 

 from the last dosing. 



EXTERNAL PARASITES. 



Parasites are the great evil of canine existence ; for if 

 the dog is not killed by internal forms, he is worried by ex- 

 ternal ones, that may be so numerous and such constant 

 companions day and night that his life is burdensome. Is 

 it possible to prevent them ? 



Lice are the pest of puppies chiefly, and are most 

 common about the head parts. Keference has been made 

 to them already. 



Fleas are divided into the common variety {Pulex irri- 

 tans) and the sand flea {.Pulex penetrans). The former 

 bites, the latter bores, into the skin. Both are believed to 

 undergo development not on the dog, but in sand, rubbish, 

 etc. 



The great difliculty practically is really not killing 

 fleas and getting rid of those on the dog at the time, but 

 in keeping him free ; in fact, the former is quite an easy 

 task comparatively. It is no exaggeration to state that 

 there are surroundings amid which it is impossil)le to keep 

 dogs clear of fleas for twenty-four hours ; so that, in choos- 



