CHAPTER VIII. 



INTESTINAL PARASITES. 



The species of worm with which puppies are most often 

 infested is the Ascaris marginata, called also the Ascaris 

 liimbricoidcs and round worm, which has a certain super- 

 ficial resemblance to the common earth-worm, or what 

 boys in the country are accustomed to term angler's worm. 

 This is cylindrical, tapers at both extremities, is slightly 

 pinkish in color, and under the knife, unless the same is 

 very sharp, offers considerable resistance, and when mature 

 cuts like India-rubber. Full growth having been attained 

 it is from two to six inches in length ; but the worms 

 found in puppies under four weeks of age usually measure 

 from two to four inches. And they much resemble pieces 

 of cotton twine. 



It is not positively known in what ways puppies acquire 

 worms, but it is highly probable that they oftentimes 

 swallow the eggs and larvae directly, also take them up 

 with their food and drink. And certainly very generally 

 the most favorable opportunities for infection are afforded, 

 as will appear from the following : — 



The eggs are laid in the intestines of their hosts and 

 expelled with the waste matters, in great numbers and 

 sometimes in great masses, and once in the world they 



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