INTERCELLULAR SUBSTAXCE. 2 / 



they are yet, probably, peculiar in each, tissue, and con- 

 stitute the greater part of the proper substance of each. 

 Commonly, when the contents are pellucid, they contain 

 granules which float in them ; and when water is added 

 and the contents are diluted, the granules display an active 

 molecular movement within the cavity of the cell. Such 

 a movement may be seen by adding water to mucus-, or 

 granulation- corpuscles, or to those of lymph. In a few 

 cases, the whole cavity of the cell is filled with granules : 

 it is so in yelk-cells and milk-corpuscles, in the large 

 diseased corpuscles often found among the products of 

 inflammation, and in some cells when they are the seat of 

 extreme fatty degeneration. All cells containing abundant 

 granules appear to be either lowly organized, as for nutri- 

 ment, e.g., yelk-cells, or degenerate, e.g., granule-cells of 

 inflammation, or of mucus. The peculiar contents of cells 

 may be often observed to accumulate first around or di- 

 rectly over the nuclei, as in the cells of black pigment, in 

 those of melanotic tumours, and in those of the liver during 

 the retention of bile. 



Intercellular substance is the material in which, in certain 

 tissues, the cells are imbedded. Its quantity is very 

 variable. In the finer epithelia, especially the columnar 

 epithelium on the mucous membrane of the intestines, it 

 can be just seen filling the interstices of the close-set cells; 

 here it has no appearance of structure. In cartilage and 

 bone, it forms a large portion of the whole substance of 

 the tissue, and is either homogeneous and finely granular 

 (fig. 14), or osseous, or, as in fibro-cartilage, resembles fine 

 fibrous tissue (fig. 15). In some cases, the cells are very 

 loosely connected with the intercellular substance, and may 

 be nearly separated from it, as in fibro-cartilage : but in 

 some their walls seem amalgamated with it. 



The foregoing may be regarded as the simplest, and the 

 nearest to the primary forms assumed in the organization 

 of animal matter ; as the states into which this passes in 



