200 



MANUAL OF HISTOLOGY. 



several drops of different sizes, and frequently very diminutive (e, g). 

 Finally, we meet with cells from which (A) all the fatty glomerules 

 of the contents have vanished, and in which the whole cavity is occupied 

 by a homogeneous liquid. 



With the decrease of the fat the nuclei become more apparent as 

 essential constituents of the cells. If the envelope, in other respects, 

 preserve its original thinness, the whole structure is very delicate in 

 contour and easy to examine. Sometimes the disappearance of the fat 

 is accompanied by another process namely, segmentation of the nuclei of 

 the different elements, until the old envelope is filled with several nuclei 

 and cells (Flemming). The same is seen in inflammation of adipose 

 tissue. 



REMAJIKS. The fact that the nucleus always reappears in cells which thus lose 

 their fats, allows of no other explanation than that in the completely-filled cells of 

 ordinary fatty tissue it is likewise present. Portions of this tissue prepared with 

 carmine, and mounted in Canada balsam after their water has been extracted, reveal 

 the presence of a nucleus also. 



122. 



As we have already seen, fat-cells are found accompanying formless, 



soft connective-tissue, whose in- 

 terstices and cavities they oc- 

 cupy. Here they form closely 

 crowded pellets of fatty tissue, 

 which are traversed by a very 

 .complex network of capillaries 

 (fig. 193, A), in each mesh of 

 which a single cell is situated 

 (B}. The energetic interchange 

 of matter which takes place at 

 times among these cells is thus 

 easily accounted for by the great 

 vascularity of the structure. 



Fatty tissue, which forms a 

 large proportion of any well- 

 nourished body, is found, first 

 of all, in subcutaneous connec- 

 tive-tissue, constituting here the 

 panniculus adiposus, and in 

 numerous other smaller and ir- 

 regular collections chiefly along 

 the course of the blood-vessels. 

 Its amount varies, however, 

 according to the region of 

 tho body. Thus large collec- 

 tions of cells are to be found 

 under the skin of tho foot, of 



the palm of the hand, of the buttocks, of the female mammary gland, 

 &c., while the eyelid is quite destitute of fat. Further, we meet with 

 an abundance of adipose tissue around the synovial capsules of joints 

 very frequently, as well as in the orbit, where it is never absent, even 

 in cases of the greatest emaciation. Again, in the medullary canal of 

 compact bones, where it constitutes the yellow marrow of the part. 

 We may mention also, among the points in the interior of the body 



Fig. 193.^. Capillary network of a pellet of fat. 

 a, the arterial; 6, the venous branch. B. Three 

 fat-cells enclosed in the meshes of the capillary net- 



