136 



LECTURE V. 



skin, which both in its continuous layer and in the 

 papillae contains nucleated cells, in direct contrast with 

 the corium proper, which at the same time is less vascu- 

 lar. But a far greater number of vessels was certainly 

 needed in the former part, inasmuch as they have at the 

 same time to furnish nutritive material for the whole 



FIG. 44. 



stratum of cuticle which lies above the papillae ; never- 

 theless, however, there is left only a small quantity of 

 juice at the disposition of the papillae as such. Every 

 papillae, therefore corresponds to a certain (vascular) 

 district of the superjacent cuticle, whilst on the other 

 hand it is itself resolved into as many elementary (histo- 

 logical) districts as there are elements (cells) in it. 



In the scrotum the subcutaneous tissue (the dartos) 

 presents peculiar interest, from the fact of its being par- 

 ticularly rich in vessels and nerves, quite in accordance 

 with the peculiar import of the part ; and besides from 

 its possessing an enormous quantity of muscular tissue, 

 consisting, in fact, of those little cutaneous muscles, 

 which I lately described to you (p. 58). These are the 

 really active elements of the contractile tunica dartos. 

 In this very part in which formerly a contractile connec- 

 tive substance was considered to exist, the quantity of 

 the little cutaneous muscles is extremely large, and the 



Fig. 44. Vertical section from an injected preparation of the skin. E. Epider- 

 mis. R. Rete inucosum. P. Papillae of the skin, with their ascending and 

 descending vessels ( loops). (7. Cutis. 11 diameters. 



