IX] HYALINE CARTILAGE 65 



I'roin which the cells have fallen out may generally be 

 seen. Except at the free edge, the cells are two or 

 more layers deep. 



The matrix is hyaline or faintly granular, and is 

 comparatively (cp. 3, 4) in small quantity. 



If the newts are not quite young there will be 

 considerable amount of matrix and it may have here 

 and there a deposit of lime salts ; the cells will be 

 chiefly in groups, many of them will contain fat- 

 globules, and some of them two nuclei (cp. 3, 4). 



b. Irrigate (cp. p. 13) the piece with acetic acid 1 p.c. 

 The following changes will be seen as the irrigation 

 proceeds : 



The nucleus becomes much more granular and 

 distinct. 



The cell substance becomes granular and more or 

 less hides the nucleus. 



The cell substance becomes transparent. 



The cell substance shrinks from the matrix, and 

 presents an irregularly serrated border. Note the space 

 thus formed between the cell and the matrix. 



Note. Examination of fresh tissues. When a 

 piece of tissue is examined fresh, in order to see as 

 nearly as possible its appearance during life, it must on 

 no account be washed or mounted in water, since water 

 causes rapid and extensive alteration. 



The best method, as a rule, is to remove a small 

 piece of fresh tissue as quickly as possible to a slide, 

 and to put on a cover-slip at once without adding any 

 fluid. Drying may be retarded by putting a little 

 moist blotting-paper round the edges of the cover-slip. 



