48 



THE ESSENTIALS OF HISTOLOGY. 



appear lamellar (fig. 51), and from this aspect their general shape is 

 square or oblong. They lie, as before said, in rows between the tendon- 

 bundles, and the nuclei of adjacent cells are placed opposite one another 



FIG. 52. TRANSVEKSE SECTION OF TENDON OP 

 MOUSE'S TAIL, STAINED. (175 diameters.) 



The flattened processes of the tendon-cells appear 

 in section as lines, frequently coming off at right 

 angles from the body of the cell. 



in pairs (fig. 53). The cell-spaces correspond in general figure and 

 arrangement to the cells which occupy them (fig. 54). 



FIG. 53. EIGHT CELLS FROM THE SAME TENDON AS REPRESENTED IN FIG. 51. 

 (425 diameters.) 



The dark lines on the surface of the cells are the optical sections of lamellar extensions 

 directed towards or away from the observer. 



Fibrous tissue forms the tendons and ligaments, and also certain 

 membranes, such as the dura mater, the fibrous pericardium, the fasciae 

 of the limbs, the fibrous covering of certain organs, etc. It is found 

 wherever great strength combined with flexibility is concerned. It 



FIG. 54. CELL- SPACES OF TENDON OF MOUSE'S TAIL, BROUGHT INTO VIEW BY 



TREATMENT WITH NITRATE OF SILVER. (175 diameters.) 



receives a few blood-vessels, disposed longitudinally for the most part, 

 and contains many lymphatics. Tendons and ligaments also receive 

 nerve-fibres, which, in some cases, end in small localised ramifications 

 like the end-plates of muscle, while others terminate in end-bulbs or in 

 simple Pacinian corpuscles. These will be described along with the 

 modes of ending of nerve-fibres. 



Development of connective tissue. Connective tissue is always 

 developed in the mesoblast or mesoderm of the embryo. In those 



