354 DISEASES OF THE INTESTINES. 



nately, many obstacles in the way of all their eggs hatching; 

 for if such did not exists the animal would probably be 

 " eaten up" by worms. For their germination^ certain de- 

 grees of heat and repose become absolutely necessary ; and 

 both these, in particular the last, the ova are not always in 

 situations to receive ; besides which, many of them are car- 

 ried away with the excrement, and expelled 7?er anwn ; in ad- 

 dition to others, which, from various causes — morbid secre- 

 tions, gases, deleterious matters in the aliment, &c. — turn 

 out to be rotten. Once hatched, the intestinal worm grows 

 the same as other worms, deriving its aliment by suction from 

 the animal liquids and solids, and such secretions as seem 

 especially adapted for its support. From the circumstance 

 of their dying at the time the animal containing them 

 dies, it would seem as if they did not and could not subsist 

 upon the mere alimentary matters in the intestines ; or else, 

 that they died from loss of that genial warmth, together with 

 the nutriment, furnished by vitality. Instances have been 

 known of their becoming numerous enough to cause the 

 destruction of the animal they inhabited ; but such cases 

 are very rare. In the opinion of Hurtrel d^Arboval, in all 

 animals they do more or less harm. Their end may be, 

 expulsion from the body alive, or they may die, and after- 

 wards become voided, and still entire and perfect : though, 

 should they remain in the bowels any length of time after 

 death, they would undergo change and decomposition, and 

 be voided as what is vulgarly called corruption. 



The Symptoms assigned to the presence of worms are so 

 numerous that one would think there could be no difficulty 

 in pronouncing upon them; and yet, after all, how stands 

 the matter of fact ? Why, that in no one, nor even in all 

 of them together, can we place such implicit evidence as is 

 furnished by the actual expulsion of one or more of the 

 worms themselves, along with the fseces. Those enumerated 

 by different authors are, — expressions, more or less violent, 

 of colicky pains ; attended with unusual whisking about of 

 the tail ; tenesmus ; and frequent discharge, per anum, of 

 mucus, or else of dung, enveloped in glairy mucous matter; 



