OF THE SKIN. 



125 



the hair-follicles, termed by Eylandt, arrectores pili, has been confirmed 

 by both writers, only that they find them to be more delicate (Eylandt 

 0-02, Henle 0-04 of a line). Eylandt never noticed more than one 

 bundle passing to a hair-follicle, and Henle states that they subdivide 

 upwards into many bundles of 0*004 of a line, and may be traced im- 

 mediately under the epidermis as far as the papilla?. In the scrotum, 

 in the skin of the penis, the perinceum, the areola mammce, and in the 

 nipple, Eylandt could not find smooth muscles ; and he imagines that I 

 have confounded the circular muscles of the vessels with them, a sup- 

 position which I should not have allowed myself to entertain even 

 against a beginner. Henle has seen the smooth muscles in all these 

 situations, which it is, in fact, very easy to do, though I think that he 

 goes to the other extreme in assuming the existence of smooth muscular 

 fasciculi in the hairless portions of the skin also, in the sudoriparous 

 glands, and in the vascular ramuscules (on their exterior), and, I believe, 

 that in these cases, he has been misled by fine nervous twigs, which, as 

 he himself states, may readily be confounded with smooth muscles, in 

 the boiled preparations which he employed. 



35. Fat-cells. These cells are especially developed in the pannicu- 

 lus adiposus. In this situation the fat-cells do not form large conti- 

 nuous expansions, but occupy, in larger or smaller clusters, the variously 

 formed meshes of the connective tissue (Fig. 45/). Each of the yellow 

 clusters, or fat-lobules, which appear to the naked eye clearly defined, 

 has a special coating of connective tissue, in which the vessels intended 

 for the nutrition of the fat-cells are distributed, and consists either of 

 a simple aggregation of cells, or of a number, varying according to its 

 size, of smaller and smallest lobules, each of which again has its proper 

 delicate investment of connective tissue. According to Todd and Bow- 

 man, every cell even, has its own special covering and vessels ; but this 



though true in many 



D . . J 



cases, is certainly not so 

 in all. In the corium 

 the fat-cells are found 

 more in the deeper part 

 round the hair-follicles 

 and sebaceous glands, 

 while they are wholly 

 wanting in the pars papillaris. In persons in tole- 



Fia. 50. Normal fat-cells from the breast ; magnified 350 diameters : a, without reagents ; 

 6, after being treated with ether, whereby the fat is exhausted, and the folded delicate 

 membrane remains. 



FIG. 51. Fat-cells with crystals of margarin ; magnified 350 diameters: a, cell with a 

 star of crystalline needles, as they maybe found not uncommonly in normal fat; 6, cell quite 

 filled with crystals, from the white fat-lobules of an emaciated subject. 



Fig. 50. 



Fir 51 





