LESSON VII. 

 CONNECTIVE TISSUE (Concluded). 



(a) Cross-Section of Ligamentum Nuchae. 



Small pieces of the ligamentum nuchse of an ox were hardened 

 in picric acid, stained in borax carmine, embedded in paraffin, and 

 sectioned. Fix to the slide and mount. 



The cut ends of the yellow elastic fibres have an irreg- 

 ular angular shape. They are grouped into larger or 

 smaller bundles. These bundles are separated from each 

 other by a small amount of white fibrous tissue. Here and 

 there a connective tissue cell between the yellow elastic 

 fibres is to be noticed. Sketch as seen under high power. 



(b) Longitudinal Section of Ligamentum Nuchse. 



The section was prepared as above, and longitudinal sections 

 made. Fix to the slide and mount in balsam. 



Observe the anastomosing fibres of yellow elastic tis- 

 sue. Sketch as seen under high power. 



(c) Embryonic Connective Tissue. 



The umbilical cord of a human foetus was hardened in a satu- 

 rated aqueous solution of mercuric chloride, stained in Delufield's 

 hsematoxylin, embedded in paraffin, and sectioned. Fix to the 

 slide and mount in balsam. 



The umbilical vessels will be seen occupying the central 

 part of the section. In this section, however, the connec- 

 tive tissue is to receive special attention. Observe the- 

 branched connective tissue cells with their long processes. 

 The cells are separated by a large amount of a granular, 

 intercellular ground substance, in which fine connective 

 tissue fibrils, as well as the highly refractive elastic fibres, 

 may be seen. Make a sketch as seen under high power. 



