IV. HISTOLOGY OF SKELETAL TISSUES 
A. TENSILE OR CONNECTIVE TISSUES. 
i. Loose Forms. 
Make a preparation of fresh areolar tissue by spreading out on 
a slide by means of mounted needles, a little of the subcutaneous 
connective tissue or intermuscular septum from any available 
mammal {e.g., cat or rabbit) and when the film thus spread is dry 
enough to remain in place, add a drop of physiological salt solution 
and cover with a cover-slip. Select a thin region of the prepara¬ 
tion. Examine first with low power, and then with high power. 
Note large amount of intercellular substance in the form of 
collagenous fibers and elastic strands. The fibers occur always in 
bundles and are often so fine and delicate that the high power 
must be used to bring out the component fibers of a bundle. The 
bundles usually appear in wavy lines, and frequently branch, 
although the individual fibers do not branch. The elastic strands 
are highly refractive in character, and by their abundant branch¬ 
ing and anastomosing form a reticulum. 
Irrigating the preparation under the cover-slip with a 2% solu¬ 
tion of glacial acetic acid serves to render the elastic reticulum 
more conspicuous, since the acid swells the bundles of collagenous 
fibers and causes them to gradually disappear from view. The 
nuclei of the scattered cells of the tissue may also become more 
conspicuous under the action of the acid. 
To bring the cells more clearly into view, the preparation may 
now be stained under the cover-slip with methylene blue, or a 
fresh preparation may be made and thus stained. Note the irreg¬ 
ular form of the cells, which are mainly of the lamellar type. 
Can you determine any definite relationship of the cells to either 
of the intercellular structures? 
Make drawings to show clearly your conception of each sort of 
intercellular structure of areolar tissue and the relation of the cells to 
these. 
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