XVII.] INTESTINE. BILE. PANCREATIC JUICE. 181 



They will be more fully studied under Lym- 

 phatics (Lesson xvm. 1, 2, 3). 



2. Snip off a few villi from a fresh intestine ; tease 

 out some in normal salt solution; place others in 

 osmic acid 1 p. c. for half an hour, then tease 

 out in water or in dilute glycerine. 



Observe more closely the characters of the cells 

 ( 1 a (a) (/3)). It will be seen that some of the 

 isolated columnar cells branch at their attached 

 ends; and that the goblet cells have usually a 

 tapering process. Where a surface view of a 

 portion of mucous membrane is obtained the 

 goblet cells will appear as clear round spaces. 



3. Prepare sections of the ileum or jejunum through 

 the glands of Lieberklihn parallel to the surface, 

 and compare them with the vertical sections 

 ( 1, t>, c). 



4. Prepare vertical sections of the duodenum at its 

 commencement close to the pylorus. In addition 

 to the villi and intestinal glands, note 



The glands of Brunner 1 . Each has a duct 

 with basement membrane, short columnar epi- 

 thelium and usually distinct lumen; the duct 

 runs down into the sub-mucous tissue and there 

 divides and sub-divides, the end tubes enlarging 

 slightly, like small alveoli ; the number of sub- 



1 Brunner's glands stretch some little distance from the pylorus in 

 ruminants and in the pig; in carnivora and rodents they are close 

 to the pylorus and usually small ; in the mole they form a marked 

 bulging ring just below the pylorus. 



