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HISTOLOGY OF ANIMALS. 
FIBROUS TISSUE. 
The fibrous, or filamentous form of tissue, enters 
largely into the construction of tendons, ligaments, 
fasciae, and other analogous parts ; it is of two 
kinds, called from their respective tints, white and 
yellow. Examples of white fibrous tissue are best 
obtained from tendinous structures, which are almost 
entirely composed of it. For the yellow, in an isolated 
condition, we resort to the lig amenta subjlava of the 
human spine, or the lig amentum nuchce of the lower 
animals. The tissue termed areolar, or the cellular 
tissue of the old anatomists, is composed of an intricate 
interlacement of the white and yellow fibres. The 
white fibres, which are most conspicuous in the natural 
state, may be made to disappear by the addition of 
acetic acid, so that the yellow fibres, which remain 
unaltered, can then be separately examined. The 
areolar tissue is more extensively diffused than any 
other throughout the animal body ; it forms the con- 
necting material between organs and tissues, and in some 
instances is found in such quantities in the Elephant, 
between the walls of the chest and the costal layer of 
the pleura, that it may be taken out by handfuls. The 
areolar tissue from the thorax of the Elephant, affords 
an excellent object for the exhibition of the nature and 
appearance of the white fibrous tissue, which occurs 
