GLANDULAR EPITHELIUM 



59 



Observe the cilia on the free border of the cells. Interspersed 

 between ciliated cells, much -enlarged individuals may be found 

 the so-called beaker, goblet, or mucous cells. 



The motion of the cilia may be demonstrated as follows: 

 Carefully open an oyster so as to preserve the fluid. On exam- 

 ination you will notice the gills, shown in Fig.. 34, commonly 



FIG. 34. OYSTER, OPENED TO SHOW METHOD OF PROCURING LIVING CILIATED CELLS. 



A. The divided muscle. This must be sectioned before the shell can be opened 



B. The heart. 

 0. Liver. 



D, D. The so-called "beard." These laminae are covered with cells provided with cilia; and 

 a fragment of the free border of one of the leaflets may be snipped off with the scissors and 

 examined as described in the text. 



called the beard. With the scissors snip off a fragment of the free 

 border of this beard, add a drop of the liquid from the oyster, and 

 tease with a pair of needles. Apply the cover, and focus (H). 



At first the individual cilia cannot be demonstrated on account 

 of their rapid vibration. After a few moments, however, the 

 action becomes less energetic, and the hair -like appendages of the 

 cells are to be plainly seen. 



GLANDULAR EPITHELIUM 



Scrape the cut surface of a piece of liver; place the scrapings 

 on a slide; add a drop of normal salt solution (vide formulae) ; mix 

 with a needle, and put on the cover -glass. 



With H observe, among the numerous blood -corpuscles, fat- 

 globules, etc., the polyhedral liver -cells, about twice or three times 

 the diameter of a white blood -corpuscle (Fig. 35). Notice the 

 large spherical nuclei, with nucleoli. Note, also, the yellow 



