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striped muscle cells. Beneatli this coat is a loose fibro- 

 elastic coat, the submucosa, in which several quite large 

 arteries and veins will be sin-n in section. The muscle 

 coat is composed of an inner circular and an outer longi- 

 tudinal layer of non-striped muscle tissue. The serous 

 coat is seen as a thin layer of fibrous tissue, covered on the 

 outer surface by a layer of endothelial cells. Sketch the 

 section by the side of the drawing of the pyloric end of tlie 

 stomach. 



(g) Small Intestine Showing: Peyer's Patch. 



A jiieceof tlie 8in;ill intestine knnu ii to eon tain a LVyer's puteh 

 was lianlened in iiiefcuiic ciiloriile, st:iine<l in Delnlield's iiivinatoxy- 

 Hn, enihedded in parallin, and siH'tiuiied. Fix and mount in 

 balsam. 



Study under low power. Observe the several nodules 

 of simple adenoid tissue in the mucosa and submucosn, 

 pushing aside the crypts of Lieberkiihu, and often coming 

 up under the epithelial lining of the intestine and causing 

 an elevation of the epithelial layer. Sketch a portion of 

 the intestine showing a lymph nodule as seen under low 

 power. 



(h) Injected Small Intestine. 



Tiie mesenteric artery of a c. t was injected witii <r(datine- 

 carmine, iiai-dened in alculidl, stained in Delalidd's ii;eniat(jx\ Un, 

 embedded in paraffin, and crods-sectioned. Fix and nionnt in 

 balsam. 



Use low power. Note the arrangement of the in- 

 jected vessels in the t)uiscular coat, in the sul)mucosa, 

 about the crypts of Lieberkiihn, and in the villi. Sketch 

 a portion of the wall under low ])Ower. 



(i) Large Intestine. 



Pieces of tlie lar^^e intestine of aduj:- were liardened in alcoliol, 

 stained in l)orax carnune, (Mnheddcd in parallin, and sectinned. 

 Fix to the slide, and nicmnt in liaisam. 



Notice that in the hirge intestine no villi are ft)un(l. 

 Simple tubular glands, the crypts of Lieberkiihn, are 

 ol)served. They are placed vertically in the mucosa, and 

 are lined by a single layer of short cohimnar cells, the 

 great majority of these appearing as goblet cells. Sketch 

 ))y the side of the small intestine as above directed. 



