39^ . PRACTICAL HISTOLOGY. fxxxvin. 



(b.) A silver nitrate preparation may also be made (p. 151). 



9. Endothelium of Mesentery. Place pieces of mesentery in 

 AgX0 3 (.25 per cent.) for half an hour, wash in distilled water and 

 expose to light in 50 per cent, alcohol. 



Part may be afterwards stained in hsematoxylin. 



10. Endothelium of Great Lymph-Sac. Open the abdomen 

 from the front along the middle line, turn aside the intestines, 

 and note the kidney. A thin membrane or septum stretches from 

 this to the abdominal wall. With a fine pipette filled with silver 

 nitrate solution perforate this membrane and allow silver nitrate to 

 flow into the great lymph-sac. Expose the membrane to light, and 

 then examine in glycerine to see endothelium and stomata (p. 239). 

 One-ha^f may be stained with hsematoxylin to show the nuclei. Or 

 expose the septum from behind as directed at p. 238. 



11. Adipose Tissue. Use the yellow-coloured fat bodies found 

 in the abdominal cavity. 



(a,) Tease a piece in glycerine. 

 (b.) Use osmic acid (p. 169). 

 See also other methods in Lesson XII. 



12. Striped Muscle. In this one must demonstrate 

 (a.) Sarcolemma (p. 193). 



(/>.) Nuclei, e.g., by acetic acid (p. 194). 



(c.) Sarcous substance with its cross stripes. Harden for half 

 an hour in alcohol and stain with hasmatoxylin or picro- 

 carmine, or both. Mount in glycerine. Osmic acid 

 also "fixes" the stria tion. 



(d.) Fibres may be isolated by means of 33 per cent, caustic 

 potash, but they must be examined in the same solu- 

 tion. 



13. Cardiac Muscle. Isolated cells are obtained by the 33 per 

 cent, caustic potash method. The fresh tissue teased, stains well in 

 picro-carmine. 



14. Smooth Muscle. Use 



(a.) Frog's bladder (p. 190). In addition, spread out the 

 bladder on a slide, expose it to the vapour of glacial 

 acetic acid, wash away the epithelium, stain with 

 violet-B, and mount in picrate-glycerine (S. Mayer). 



(6.) Intestine. The muscular coat alone is to be used, after 

 scraping away the mucous coat. Treat it as above. 



15. Epithelium. Scrape any epithelial surface, diffuse the 

 scrapings in normal saline and examine fresh, and seal up with 

 paraffin wax. 



Squamous. Use cornea. 



Columnar. Use intestine. 



Ciliated. Mucous membrane of palate. 



