214 SPECIAL HISTOLOGY. 



each hair of the scalp; they are somewhat larger, 0-16-0*24 of a line 

 in the hairs of the beard, and the longer hairs of the chest and axilla, 

 in which situations several glands are usually disposed around the hair 

 follicle ; the largest of all exist on the mons veneris, the Idbia majora, 

 and the scrotum, where, at all events in the last-mentioned locality, they 

 are found at the deepest boundary of the corium, and the glands, from 

 four to eight being connected together, represent beautiful rosettes J J 

 1 line broad. Attached to the sacs of the smaller coarse hairs, I find 

 smaller sebaceous glands of 0-06-0-24 of a line, mostly in pairs; and 

 also in the eyebrows, eyelids, and the hairs at the entrance of the nos- 

 trils. The lanuginous hairs have generally larger glands, or aggrega- 

 tions of glands of J 1 of a line ; these are best displayed in the nose, 

 the ear (concha, fossa scapJioidea), the penis (anterior half), and the 

 areola mammce, especially in the first of these situations, where the 

 glands often attain a colossal size, and altogether peculiar forms (Fig. 

 85) ; the glands generally have a diameter of -J J of a line on the 

 caruncula lachrymalis, the lips, brow, thorax, and abdomen ; they are 

 somewhat smaller, -J J- of a line, but almost always larger than in the 

 hairs of the scalp, in the eyelids, cheeks, neck, back, and extremities. 

 Of the glands which are not connected with hair-sacs, only a portion of 

 those of the Idbia minor a are of large size (0*14 0*5 of a line) and 

 rosette-shaped, with an aperture of 0*083 of a line ; the others are for the 

 most part simply tubular, and at most 0-12-0-16 of a line long, 0-04- 

 0-06 of a line broad. The glandular vesicles of the sebaceous glands 

 are either round, or pyriform and flask-shaped, or even elongated or 

 tubular. Their size varies exceedingly, from 0-06-0-16 of a line in 

 length, 0-02-0-1 of a line in breadth, and is in the mean 0-04 of a line in 

 the round ones ; 0'08 in length, and 0-03 of a line in breadth in the others. 

 The excretory ducts also have very different dimensions, sometimes long, 

 sometimes short, broad or narrow ; the principal excretory ducts measure 

 in the nose and Idbia minor a up to j- of a line in length, 75 i f a li ne 

 in breadth, and have an epithelium 0-015-0-03 of a line thick. 



The sebaceous glands on the glans penis, and on the inner lamella of 

 the prepuce or " Tyson's glands," are very inconstant, occurring some- 

 times only in a very small number, sometimes in hundreds. They are 

 ordinary sebaceous glands, which are distinguished from those of other 

 regions by their not being connected with hair-sacs, and by their open- 

 ing independently on the surface of the skin. They may, generally, be 

 perceived by the naked eye as small whitish points, which do not project 

 above the skin ; and in sections of the skin treated with caustic soda or 

 acetic acid, their peculiarities may be readily studied with the micro- 

 scope. They appear to be sometimes tubular, at others, simply racemose ; 

 the former present a round or pyriform follicle of 0-048-0-12 of a line 

 in diameter, and a straight excretory duct of -^ of a line in length, and 



