Gelatineous

When it has arrived at this stage, the internal gelatineous substance, which is extremely vascular, deposits, or rather, seems converted, on its most prominent points or edges, into an osseous matter, which is at first soft and elastic, but hardens by degrees into the bony substance described above; […]

The electron-microscopy however does not add very much to our knowledge of those suprastructures which consist mainly of a gelatineous mass rich in mucopolysaccarides. […] In addition we find in the otolithic membrane the otoliths on top of and imbedded in this gelatineous mass as hexagonal calcite cristals of different size.

It [oxtail] is sold cut into pieces and, while meaty, it is also bony, and contains plenty of connective tissue that breaks down into a gelatineous liquid during slow cooking, such as braising. […] A marrow bone added to a stock pot will lend a gelatineous, silky texture and a deep flavour.