190 LECTURE IV. 



whilst the excrementitlous matter alone 

 remains loose in the calibre of the intes- 

 tines, and at liberty to be urged on by 

 their peristaltic actions. Nay, Mr. Cooper 

 further showed us that the same circum- 

 stances also obtained in the large intes- 

 tines, that portion of the alimentary matter 

 which could be modified and rendered meet 

 for absorption, acquiring an adhesive pro- 

 perty and clinging to tlie surface, which 

 accomplished these purposes. 



It is well known that a sreat and sudden 

 change is \vrou"hfc in the contents of the 

 alimentary canal, immediately on its transit 

 from the small into the large intestines, 

 that a valve is formed to prevent any com- 

 munication between them in a retrograde 

 course ; that the commencement of the 

 large intestines, usually called the caecum, is 

 in herbivorous animals particularly capa- 

 cious, and apparently calculated for detain- 

 ing the alimentary matter; and in some, as 

 in the horse, this portion of the alimentary 

 canal is of surprising magnitude ; that the 

 extent of surface of the linino- of the large in- 



