88 ELEMENTARY PHYSIOLOGY 



The chinks and spaces of the tissues are filled with that 

 fluid exudation from the blood-vessels and tissue elements 

 already spoken of as lymph, and hence are themselves 

 often called lymph-spaces. In these lymph-spaces we 

 see the origin or beginning of the lymphatic system. 



From the lym))h-spaces thelympli passes into tlie lymph 

 capillaries. These are also essentially spaces in the mesh- 



\- 



N \ /^, , ,:f,,.^ 





Fig. 28.— Connective Tissue Fibres. 



a, small bundles of white fibrous tissue ; b, larger bundles ; c, single 

 elastic fibres. 



work of connective tissue, but they are now lined by a 

 single layer of extremelj' thin, flat, nucleated, epithelioid 

 cells, very similar to those composing the wall of a blood 

 capillary, but cliaiacterised by their edges being very 

 sinuous or indented. These cells are joined to each other 

 by their edges, tlie sinuosities of adjacent cells fitting into 

 one another, so tliat tliey form a system of minute tubes, 

 larger than blood-capillaries and wandering more irregu- 

 larly. 



