84 LECTURES. 



Whenever, or by whatever mode the eggs are 

 conveyed to the mouth, their subsequent passage 

 to the stomach insures their being hatched, and the 

 little vermiform embryos are soon transferred to the 

 duodenum and other divisions of the small in- 

 testine. In this situation the embryos undergo still 

 more remarkable transformations, casting their 

 skins, and growing with great rapidity ; being at 

 length conveyed to the csecum, which constitutes, 

 so to speak, their head-quarters. It is quite an 

 error to suppose the lower bowel or rectum forms 

 their especial habitat; nevertheless you will find 

 statements of this kind in the most approved 

 manuals, vade-mecums, general treatises, and spe- 

 cially contributed articles. 



As regards the organization of the adult worm, 

 I must refer you again to my larger treatise, and 

 more especially also to the admirable monographs 

 by Professor Bastian, and to a paper by my col- 

 league Mr. Lowne. 



The symptoms produced by the presence of 

 Oxyurides in the caecum and large intestine, though 

 seldom or never fatal to the bearer, are occasionally 

 very serious ; whilst in the mildest cases they have a 

 tendency to undermine the general health. As 

 I have observed elsewhere, the unpleasant sensa- 

 tions chiefly develop themselves in the evening 

 and at night, consisting for the most part of 

 sensations of heat and irritation within and around 



