19 



Place a small drop of the glycerin on a slide and cover with a 

 cover-glass. Search the preparation to find (a) completely isolated 

 cells, {6) cells adhering together in clusters and affording a surface 

 view of the epithelium. Note as before the shape and structure of 

 the cells and the shape and position of the nucleus. Try to find 

 goblet cells. 



CIIvIATED EPITHELIUM. 



8. Ciliated cells from the trachea. Cat. Two preparations 

 made last week. 



Carefully clean around the cover glass and seal with shellac 

 (§ no). Study the preparations, searching for completely isolated 

 cells and cells adhering in clusters. Note the shape of the cells, the 

 structure and position of the nucleus, the cilia, the shape of the 

 basal end. Compare the two slides, noting the identity of structure 

 but different staining. 



g. Ciliated cells from the trachea. Horse. Isolated in Miil- 

 ler's fluid dissociator ; stained with , now in 



Mount in glycerin jelly (§ 105). Study carefully, noting the shape 

 of the cells, the shape and position of the nucleus, the length of the 

 cilia. Compare with 8. 



10. Ciliated epithelium. Section of the soft palate. Cat. 

 Assigned for study. 



The nasal side will show a so-called stratified ciliated epitheli- 

 um. Observe the cilia covering the free ends of the cells ; compare 

 the, apparently, superficial cells bearing the cilia with the deeper 

 cells. Examine 8 again to see if you can find any isolated cells of 

 the deeper layer. 



11. Living ciliated cells. Go to the desk with a slide for 

 living ciliated cells from the oral epithelium of the frog. Place 

 upon the slide in a drop of saliva or normal salt solution ; cover. 

 Study the activity of the ciliated cells, trying to ascertain the move- 

 ments of the cilia. This may best be done in cells in which the cil- 

 iary movements have considerably slackened. 



12. Living ciliated cells. From the trachea. Cat. Demon- 

 stration. Observe the ciliary movements, noting the rate and direc- 

 tion of the vibrations. 



13. Ciliated pavement epithelium. From the peritoneal 



