140 SEBACEOUS GLANDS. [sect. 75. 



are placed singly or in pairs on the hair-follicles. In the new-born 

 infant, simple clusters, of o'i w to 0-12'" in length, and only 0-04'" 

 to 0-06'" in breadth, and disposed singly, or more rarely in pairs, 

 upon the follicle, are found in place of the simple tubes. It is 

 only on the chest, ear, temples, nose, nipple, the labia majora, and 

 the scrotum, that they are rosette-shaped; they here measure 

 o-i'" in diameter, and, in the four last-mentioned places, even up 

 to 0-4'" and more. From these statements, it appears that most 

 of the glands continue to increase after birth ; certain glands are 

 only developed after birth, as, for example, those of the labia 

 minora. 



The sebaceous glands occur also in abnormal positions. Thus Kohlrausch 

 observed them in an ovarian cyst, and v. Bdrensprung in a subcutaneous en- 

 cysted tumour of the forehead ; and in both places they were associated with 

 hair-follicles ; whence it may be concluded, that they are, perhaps, often 

 present in cysts which contain hairs. In fact, I met with very beautiful 

 sebaceous glands, with much sebaceous matter in the walls of the before- 

 mentioned hair-containing cyst in the lungs. V. B'drensprung believes he 

 has seen, though rarely, a new formation of the sebaceous glands in cicatrices 

 of several years' standing. When the hairs fall out, the sebaceous glands 

 seem to disappear ; at least, I have frequently noticed that they were wanting 

 in bald spots. According to E. H. Weber, hypertrophy of the sebaceous 

 glands takes place in cancer of the skin ; according to v. Bdrensprung, in 

 alirothymion, or moist warts, and in ncevus pilosus. The comedones, also, 

 among which I rank the lichen pilaris, at least, as defined by Simon, are hair- 

 follicles and sebaceous glands, filled with and dilated by sebaceous matter. 

 They especially occur in places where the glands are distinguished for their 

 size, as on the nose, lips, chin, ear, areola of the nipple, and the scrotum, 

 and arise either from obstruction of the openings of the • hair-follicles by 

 sordes, or from viscidity and tenacity of the secretion. They contain — 

 besides one or several hairs, which, however, may also be absent — fat-cells, as 

 in the normal sebaceous matter, epidermis-cells from the hair-follicles, free 

 fat, frequently crystals of cholesterine and the acarus folliculorum. 



Milium. The small white spots or nodules termed milium, found on the 

 eyelids, the root of the nose, the scrotum and ear, are likewise formed, as v. 

 Bdrensprung justly assumes, from the sebaceous glands ; that is, when the 

 latter alone, without the hair-follicles, dilate, whence rounded prominent nodules, 

 without any aperture, are produced, with contents resembling those of the come- 

 dones, which may frequently be pressed out through the hair-follicles. Lastly, 

 the sebaceous cysts, which have their seat in the cutis itself, must undoubtedly 

 be regarded as enormously enlarged hair-follicles, with the sebaceous glands. 

 For particulars concerning these, we refer the reader to the works already 

 cited ; also, with regard to a small parasite, the acarus folliculorum, which 

 inhabits both healthy and enlarged hair-follicles and sebaceous glands, G. 

 Simon (1. c, p. 287) may be consulted. In the before-mentioned case of 

 ichthyosis congenita, Dr. H. Mullcr and I found the excretory ducts of the 

 sebaceous follicles in the epidermis everywhere enlarged, of 0-03'" to 0-06'" 



