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(d) Teased Involuntary Muscle. 



The muscular coat of the small intestine of a cat was macerated 

 for 15 minutes in a 30% solution of caustic potash, then placed in a 

 saturated solution of acetate of potash. Teaso in gum glycerine. 



Observe the long, fusiform or spindle-shaped cells 

 with rod-shaped nuclei. The protoplasm often shows a 

 longitudinal striation. Sketch several under high power. 



(e) Section of Involuntary Muscle. 



The muscular coat of the small intestine of a cat was hardened 

 in absolute alcohol, stained in Delafield's hsematoxylin, embedded 

 in paraffin, and sectioned. Fix and mount in balsam. 



The fibres in the longitudinal coat will appear in cross 

 section ; note that they vary in size, and only a few are 

 nucleated (many cross sections can be made of a single 

 cell, but very few of them will pass through the nucleus). 

 The circular layer is cut in the directiori of the longitudi- 

 nal" axis of the cells. Sketch under high power a portion 

 of both coats. 



