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HANDBOOK OF PHYSIOLOGY. 



a matrix. The cells, which contain a nucleus with nucleoli, are irregular 

 in shape, and generally grouped together in patches (fig. 53). The 

 patches are of various shapes and sizes and placed at unequal distances 

 apart. They generally appear flattened near the free surface of the 

 mass of cartilage in which they are placed and more or less perpendicular 

 to the surface in the more-deeply seated portions. 



The matrix of hyaline cartilage has a dimly granular appearance like 

 that of ground glass, and in man and the higher animals has no appar- 

 ent structure. In some cartilages of the frog, however, even when ex- 

 amined in the fresh state, it is seen to be mapped out into polygonal 

 blocks or cell-territories, each containing a cell in the centre, and repre- 



Fig. 53. 



Fig. 54. 

 The cell bodies entirely fill the spaces in the 



Fig. 53. Hyaline articular cartilage (human), 

 matrix. X 340 diams. (Schafer.) 



Fig. 54. Fresh cartilage from the Triton. (A. Kollett.) 



senting what is generally called the capsule of the cartilage cells (fig. 

 54). Hyaline cartilage in man has really the same structure, which can 

 be demonstrated by the use of certain reagents. If a piece of human 

 hyaline cartilage be macerated for a long time in diluted acid or in hot 

 water 35-45 C. (95-113 F.), the matrix, which previously appeared 

 quite homogeneous, is found to be resolved into a number of concentric 

 lamellae, like the coats of an onion, arranged round each cell or group 

 of cells. It is thus shown to consist of nothing but a number of large 

 systems of capsules which have become fused with one another. 



The cavities in the matrix in which the cells lie are connected to- 

 gether by a series of branching canals, very much resembling those in 

 the cornea: through these canals fluids may make their way into the 

 depths of the tissue. 



In the hyaline cartilage of the ribs the cells are mostly larger than 

 in the articular variety and there is a tendency to the development of 

 fibres in the matrix (fig. 55). The costal cartilages also frequently be- 



