DISEASES OF DOGS— WORMS. 48 1 



from the body, and by strengthening the system generally, par- 

 ticularly the alvine canal. In every case the bowels should be 

 kept freely open, or the vermifuges will not act successfully. 



The list of vermifuges is almost interminable. They may be 

 conveniently divided into two classes : 



1. Those that dislodge and drive away intestinal worms by 

 some mechanical or other external action ; as all drastic purges, 

 all oleaginous vermifuges as oil of beech nuts, castor, sulphur, pe- 

 troleum, sea salt, tin filings, powdered glass, pomegranate root, 

 kamela, areca nut, koosso, and the down of the pods of cowhage. 

 The last four more particularly act by setting up an inflammatory 

 condition of the bowels, which are remedies the effects of which 

 are frequently more to be deplored than the disease. 



2. Those that destroy them by killing before they are expelled ; 

 as the male fern, hellebore, fetid hellebore, cevadilla, Chabert's oil 

 (obsolete), tansy, savine, rue, dittany, tobacco, wormseed and its 

 active principle santonine, oil of turpentine, the bark of the bulge- 

 water tree and of the cabbage tree, the spigelias, and Indian scab- 

 iosa. Many of these are hardly worth noticing ; while others are 

 most effectual in the elimination of tape worms ; savine, rue, tansy 

 and tobacco must be avoided in pregnant animals, and at best are 

 very uncertain in action. Of the prescriptions at the end of the 

 section, i represents the best of the first ; and 2 and 3 of the second. 



Thread Worm. — This a small, white round worm, which is 

 tapered off at both ends. They vary in length from three to twelve 

 millimetres *. The embryos are hatched in the rectum, and ap- 

 pear to betake themselves almost immediately to the upper por- 

 tion of the small intestine, where they rapidly increase in size, 

 obtaining their nourishment from the chyme and the intestinal 

 mucus. As soon as they attain a certain size, some of the young 

 worms have sexual intercourse while here residing ; others how- 

 ever, descend into the caecum for this purpose. In favorable cases 

 one finds large numbers of females in every stage of development, 

 in the small intestine, and in the caecum, with a like number of 

 males. The young fructified females gradually collect in the cas- 

 cum, and live there for considerable time, — until they are full- 



* I use the French measurement as the English is not sufficiently fine for the 

 purpose. 



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