38 



VETERINARY PHYSIOLOGY 



makes its appearance, forming a soft, jelly-like tissue. It 

 contains an abundance of mucin (p. 35). This tissue is 

 widely distributed in the embryo as a precursor of the con- 

 nective tissues, and after birth it is still to be seen in the 



Fig. 8. — Mucoid Tissue from an embryo rabbit. 



pulp of a developing- tooth and in the vitreous humour of 

 the eye (iig. 8). 



2. Fibrous Tissue. — As development advances, the cells of 

 mucoid tissue elongate and become spindle-shaped, and are 



FiC4. 9. — Fibroblasts from voung fibrous tissue. 



continued at their ends into fibres (fig. 9). These cells are 

 often called Jibrohlasts. 



The connective tissues are thus clearly distinguished from 

 the epithelia by having the formed material bettueen and 



