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E. T. Bell. 



of a fat lobule. These cells have lost their processes and become 

 rounded. Cell B has a large amount of protoplasm, but only a little 

 fat. This multiglobular cell is somewhat similar to the cells of brown 

 adipose tissue. In both cells the cell membrane is readily seen. 



Figure 10, Plate 11, was drawn from the inguinal adipose tissue 

 of a 32 cm. foetus. Fat cells of different stages of development are 

 shown. Most of the smaller cells are of the type shown in Text 

 figure 9 — rounded cells with considerable granular protoplasm and 



Text Figure 8. Two younj; fat cells from the renal adipose tissue of a 

 42 cm. foetus. The cells lie well into the edge of the lobule, f, spaces occu- 

 pied by fat droplets; g, Altmann granules; m, cell membranes; n, nucleus; 

 /)/•. processes of cell. Fixation, Zenker's fluid. Stained with iron-hipm. and 

 eosin. x 1200. 



Text Figure 9. Two young fat cells from the renal adipose tissue of a 

 42 cm. foetus. The cells lie well into the edge of the lobule, f, spaces occu- 

 l)ied by fat droples; g, Altmann granules; m, cell membrane; rt, nucleus. 

 Fixation, Zenker's fluid. Stained with iron-hinem. and eosin. x 1200. 



one or more fat droplets. Most of these cells were not derived directly 

 from the original branched cells of the preadipose tissue, but from 

 the division of small cells in the interior of the lobule. As will be 

 described later, the fat lobule grows, in its early stages at least, by 

 division of small fat-free cells inside the lobule as well as by the 

 addition of cells on its periphery. The cells formed inside the lobule 

 are not branched; they become rounded directly by increasing their 

 protoplasm and accumulating fat. The largerx^ells (about 25 microns 



