294 Prof. V. Harley. Influence of Removal of Large Intestine and 



more valuable since in the presence of bile it gives a bright green 

 colour, in consequence of the conversion^ bilirubin into biliverdin by 

 the perchloride of mercury. 



Since this method has been introduced it has become possible to 

 recognise very small quantities of urobilin in the faeces. 



Schmidt, examining by this method the different parts of the intes- 

 tine and intestinal walls, showed that the urobilin reaction yielded 

 results proving that in different parts of the intestine urobilin was 

 present in varying degree, and also varied in different cases. The 

 staining of the intestinal walls by this method, he considered, indicated 

 the parts of the intestine which took part in the absorption of urobilin .. 

 My own experiments on dogs and monkeys, in which the post mortem 

 examination was made immediately after death, showed no such stain- 

 ing of the walls, and therefore I consider it was probably due to a pos,fe 

 mortem diffusion. 



The test, however, is valuable for the determination of urobilin ia 

 the contents of .the bowel, and this we will now consider. 



I noted in various animals that as a rule no trace of urobilin could 

 be found in the contents of the intestine above the ileo-caecal valve.- 

 In some few dogs there was a trace of urobilin in the contents just 

 above the caecum, but in the majority of normal dogs recognition o 

 this substance was only possible after the ileo-csecal valve was passed. 



Of the dogs in which the large intestine had been removed, dog 5 

 was killed by chloroform and the contents examined. In this dog the? 

 post mortem showed the small intestine to have been artificially joined 

 to the rectum 6 cm. from the anus ; and 78 cm. from the anus the 

 green colour was first noticed by the perchloride of mercury reaction, 

 and then, 35 cm. from the anus, began to show the urobilin reaction., 

 which extended as far as the anus. 



In dog 4 only 4 cm. of the rectum was found remaining at the 

 post mortem, and this dog only showed a very faint urobilin reaction 

 in the contents of this latter 4 cm. That is to say, throughout the. 

 entire small intestine of this dog no reaction of urobilin could be 

 obtained. 



These post mortem results were borne out to a certain extent by 

 observations during life. It was found in most of the dogs, in which* 

 the large intestine had been removed, that immediately after the 

 operation the motions were bile-stained, and gave the green colour 

 with perchloride of mercury, and, only very faintly or not at all, the. 

 pink urobilin reaction. Later on the urobilin became increased, and 

 the bilirubin apparently decreased. 



In dog 5, throughout the time metabolism experiments were carried 

 on, there was always more marked urobilin than in other dogs observed 

 after the removal of the large intestine. 



