21 



Lesson VI. 

 FIBROUS CONNECTIVE TISSUE, 



(a) Fibrils of White Fibrous Connective Tissue. 



One of the small tendons of a rat's tail is to be placed on a 

 clean and dry slide. Place a small piece of filter paper (about J^ in. 

 square) moistened in normal salt over the middle part of the tendon ; 

 quickly spread out the ends of tiie tendon with your teasin<r needles. 

 The spread-out ends will dry and lix the tendon to the slide. Tease 

 the middle portion in normal salt, and cover witli a slip. 



Study under high power. Observe the very fine 

 fibrillae, often slightly wavy. Notice that they neither 

 branch nor anastomose. Add a few drops of a 1% solu- 

 tion of acetic acid. This causes the fibrils to swell up and 

 become homogeneous. Sketch as seen before acetic acid 

 is added. 



(b) Fibrils of Yellow Elastic Connective Tissue. 



Tease a small portion of the elastic tissue taken from the liga- 

 mentum nuclue of an ox in normal salt solution. 



Observe the fibrils of yellow elastic tissue. They are 

 highly refractive, branch and anastomose, and the broken 

 ends curl back. Run a few drops of the acetic acid solu- 

 tion under the cover glass, and notice that the yellow 

 elastic fibrils are not afi^ected by it. 



(c) Stained Yellow Elastic Tissue, 



Small pieces of ligamentum nucha? were macerated for 3 to 4 

 days in a 1% solution of acetic acid, stained for several days in a 

 1% aqueous solution of acid fuchsiu, thoroughly washed in flowing 

 water, and placed in glycerine. Tease in gum glycerine. 



The stained fibrils will be easily made out. Sketch 

 under high power. 



