546 



THE DIGESTIVE SYSTEM. 



filling the cavity of the stomach, to which in shape it may correspond 

 (Fig. 318).' 



The Intestines. 



Malformations . 



ATUESIA ANI. Absence of the anal opening is frequent. This may be associated 

 with partial or complete atresia of the rectum or of the colon which may be represented 

 by solid cords. Blind terminations of the small intestine may occur, or there may be 

 complete closure of the gut. 



TRANSPOSITION. The position of the intestines may be the opposite to that which 

 is usually found. The transposition may affect all the abdominal viscera, or only a 

 single viscus is transposed. 



ANOMALOUS POSITIONS OF THE COLON are not infrequent. 2 



DIVERTICULA. Intestinal diverticula are most frequent in the lower part of the 

 ileum. They usually spring from the convex surface of the intestine, more rarely 

 from its attached border. In the latter case they are 

 joined to the mesentery by a fold of peritoneum. The 

 diverticulum forms a pouch from one to six inches 

 long, of about the same diameter as the intestine, small- 

 est at its free extremity (Fig. 319). 



Such diverticula do not interfere with the func- 

 tions of the intestines. They occasionally form part 

 of a hernia. Sometimes the remains of these intestinal 

 diverticula called Meckel's diverticula form soft, 

 projecting tumors at the umbilicus 3 in children. Micro- 

 scopical examination of such tumors often shows the 

 structure of the intestinal mucosa and muscularis. 

 If they remain attached by a fibrous cord to the navel, 

 this cord may be the cause of incarceration of a portion 

 of the intestines. 4 



False Diverticula. Not infrequently one finds at 

 autopsies either in the 'small or large intestine diver- 

 ticula or hernioe, which project from the exterior of the 

 gut, usually near its mesenteric attachment. These 

 consist of the mucous membrane which has been 

 crowded through the muscularis and is covered by 

 serosa. These so-called " false diverticula " may be 

 large, but are generally not larger than a pea; they 

 may be single or numerous (Fig. 320). They as a rule 

 cause no functional disturbance, but may, through 

 the accumulation of faecal material within them, be the 

 seat of perforation. 5 

 CLOACA:. The rectum may open into the bladder, urethra, or vagina. Thus 



'Such a specimen, mentioned by Osier, is in the museum of McGill University; 

 another, reported by Findler (see Fig. 318), is in the museum of the College of Physi- 

 cians and Snrgeons, N. Y. See Jacobson, Med. News, Feb. 16th. 1901 ; also Fenwick, 

 Br. Med. Jour., Nov. 29th, 1902, bibliography. 



2 For bibliography of reported cases see Shober, Am. Jour. Med. Sciences, vol. 

 cxvi., p. 405, 1898. 



3 For bibligraphy of umbilical tumors see Giannettasio, Arch. gen. de Med., t. iii., 

 p. 65, 1900. 



4 For bibliography see Reisman, Proc. Path. Soc. of Philadelphia, new ed., vol. i., 

 p. 193, 1898. For case of volvulus of Meckel's diverticulum see Taylor, Johns Hopkins 

 Hospital Bull., vol. xii., p. 326. 



5 Consult Fischer, "False Diverticula of the Intestine," Jour. Exp. Med., vol. v., 

 p. 333, 1901, bibliography. 



9. DlVKRTlCCLUM OF THE 



SMALL INTESTINE. 



