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L?:ssoN VIII. 

 CARTILAGE. 



(a) Hyaline, Fresh. 



Tliin sections are removed from the articular surface of a frog's 

 femur by a sharp razor. Mount in normal salt solution. 



Examine under high power, using one of the smaller 

 openings in the diaphragm. Observe the round or oval 

 cartilage cells, each surrounded by a capsule, and possess- 

 ing a large spherical or oval nucleus. The cells are often 

 found in groups of 2, 4 or more, and are in small spaces 

 (the lacunse) in the homogeneous, intercellular ground 

 substance, the matrix. 



(b) Hyaline Cartilage, Stained. 



The ]iea<l of a femur of a cat was divided into several pieces; 

 these were hardened in a saturated aqueous solution of mercuric 

 chloride, decalcified in a 1% solution of hydrochloric acid, stained in 

 borax carmine, embedded in iiaraftin, and cross-sections made. 



Study first under low power. Observe the hyaline 

 cartilage surrounding the cancellated bone. In the deeper 

 portion of the cartilage, the matrix is granular; this is a 

 narrow zone of calcified cartilage. Sketch the section as 

 seen under low power. 



(c) Elastic Fibro-Cartilage. 



The epiglottis of a dog was hardened in alcohol, embedded in 

 celloidin, stained in Iijematoxylin, and counter-stained in a 1% 

 aqueous solution of acid fuchsin. 



Study under low power. The nuclei of the cartilage 

 cells are stained with the hsematoxylin. An interlacing 

 network of yellow elastic fibres stained red by the acid 

 fuchsin will be seen in the ground substance. Sketch as 

 seen under high power. 



