226 SKIN, HAIR, AND NAILS, BY ALFRED BIESIADECKI. 



In the description of the corium and of the subcutaneous 

 connective tissue we have spoken of spaces that occur between 

 the fibres, and are filled with serous fluid, varying in quantity 

 with the succulency of the individual. In pathological condi- 

 tions, and both in acute and chronic exsudations, as in oedema, 

 these spaces are essentially the seat of the effused material. 



Such spaces occupying the interspaces of the fibres of the 

 corium have no proper walls ; as is shown by the fact that the 

 oedematous fluid of a wide area will discharge itself through 

 a comparatively slight cut in the skin. These spaces are 

 designated lymph spaces, although no direct communication 

 between them and the lymphatics has been demonstrated. 



The relation of the bloodvessels to the lymphatics is worthy 

 of special notice. Although the course and ramifications of the 

 larger lymphatics are independent of the bloodvessels, appear- 

 ances are frequently presented, especially in oedematous skin, 

 which tell in favour of the existence of some specific relation 

 between the two sets of vessels. Thus each lymphatic is ac- 

 companied for considerable distances by a capillary blood- 

 vessel, and not unfrequently by two, which lie in immediate 

 contact with it, or may even be imbedded in its wall to nearly 

 half their depth. According to Langer, in the skin of the Frog 

 two lymphatics accompany the larger bloodvessels. In the sub- 

 cutaneous tissue of Man these relations are so far different, that 

 in many parts, as in the penis and the extremities, the larger 

 lymphatics are accompanied by two bloodvessels, by the capil- 

 laries of which they are surrounded. 



By various writers, as by Strieker, perivascular lymphatics 

 have been described, whilst their existence has been denied by 

 others (Langer). In the human skin the bloodvessels are 

 certainly not invested by lymphatics possessing a proper wall 

 lined by epithelium. We have stated above, however, that 

 the bloodvessels, and even the capillaries, are enclosed by 

 parallel fibres of connective tissue, and fusiform connective- 

 tissue corpuscles. Between these and the vascular wall we 

 find, as elsewhere, spaces containing serum, the width of which 

 varies, and which may be quite correctly termed perivascular 

 lymphatic spaces. 





