ADIPOSE TISSUE. 



43 



under the serous membranes ; especially in some parts, as at the back 

 of the peritoneum around the kidneys, under the epicardium, and in 

 the mesentery and omentum. The yellow marrow of the bones is also 

 principally composed of fat. There is no adipose tissue within the 

 cavity of the cranium. 



Retiform or reticular tissue (figs, 46, 47)is a variety of connective tissue 

 in which the intercellular or ground substance has mostly disappeared or 

 is replaced by fluid. There are very few or no elastic fibres in it, and 

 the white fibres and bundles of fibres form a dense network, the meshes 

 of which vary in size, being' very small and close in some parts ; more 



FIG. 46. RETIFORM TISSUE FROM A LYMPHATIC GLAND, FROM A SECTION WHICH HAS 

 BEEN TREATED IN THE MANNER, DESCRIBED IN 5. (Moderately magnified.) 



tr, a trabeculum of connective tissue ; r, r 1 , retiform tissue, with more open meshes at 

 r and denser at r'. 



open and like areolar tissue in other parts. In some places where 

 the tigsue occurs the fibres are almost everywhere enwrapped by flat- 



FIG. 47. PORTION OF THE ABOVE, MORE HIGHLY MAGNIFIED. 



tened branched connective-tissue cells, and until these are removed it is 

 not easy to see the fibres. 



