AILMENTS AND ILLNESSES 53 



may be classed as tape-worms and round worms of the 

 dog are concerned. Only a few years ago, if a dog 

 suffered from skin disease in any one of its several forms, 

 " worms " were at once cited as the cause. Now we 

 know or rather, those among us know, who either have 

 some understanding of canine anatomy and physiology 

 or will take the word of the scientist for it that worms 

 cause nothing : they are not a cause, but an effect. 

 They are a symptom of anaemia ; and as skin trouble 

 almost invariably accompanies any severe degree of 

 anaemia in dogs, skin trouble and worms are usually 

 found together. We cannot, therefore, cure dogs of 

 harbouring worms by giving expellent doses, no matter 

 how glowingly advertised and boomed, of the various 

 irritant drugs which act as vermifuges. We can only 

 by this means temporarily drive out the enemy, which 

 is certain to return, because the conditions prevailing 

 in an anaemic intestine suit it perfectly, and encourage 

 its increase, whereas in the healthy intestine it more or 

 less shares the fate of food on being digested, and is 

 incapable of rapid or sustained increase. The effect of 

 an anaemic or vitiated condition of the blood-supply to 

 the villi, or, in non-scientific language, digesting pores 

 which exist all over the mucoid lining of the intestinal 

 tract, is to prevent their throwing out those strong 

 juices or digestive fluids which they normally produce. 

 Their secretions are altered and weakened, and have 

 no injurious effect on the parasites, which then in- 

 crease rapidly. When, therefore, it becomes evident, 

 by the appearance of short yellowish-white segments, 

 generally about an inch long, and varying in breadth 

 from a mere line to about a quarter of an inch, dropped 

 about by a dog, that tape-worm exists ; or it is seen by his 

 vomiting them up or otherwise, that he has round worms, 

 which somewhat resemble earth-worms, what we have 

 to do is to alter that condition of the general health 

 which allows these pests to exist. In brief, we have to 

 treat the dog for anaemia, which subject has been 

 already discussed. It is, of course, occasionally pos- 



