268 THE TISSUES. 



are an epithelial production, we should not be unprepared to find 

 them wherever an epithelium exists, though they have not been 

 found on the serous membranes. 



No hairs are developed upon cicatrices on the skin. 



The falling out of the hair of the head, constitutes baldness 

 (alopecia). When due to an atrophy of the hair-sacs, remedies are, 

 of course, of no avail. One cause of its far greater frequency in 

 men than in women, is, very probably, the style of hat so generally 

 worn, especially in this country; and which by its stiffness, its form, 

 and its heating powers, at the same time banishes all comfort, and 

 violates the principles of good taste, common sense, and physiolo- 

 gical science. 



Some diseases of the hair are produced by vegetable parasites 

 (fungi) in the interior of the hair itself. This is the case with 

 herpes (or tinea) tonsurans (Gfruby); and Dr. Jenner, of London, has 

 shown that the sulphurous acid destroys the parasite and cures the 

 four varieties of this disease. 1 In porrigo decalvans ( Willan), the 

 fungus is under and around the cuticle of the hair. (Gruby^) 



In plica Polonica, in which the hair becomes matted together, 

 and appears even sensitive, a fungus is developed, according to 

 Guensberg and Walther, in the bulb and shaft of the hairs, and 

 partly Destroys them. Munter, however, found no such fungus. 



CHAPTBK II. 



YELLOW FIBKOUS TISSUE. 



The yellow fibrous tissue (elastic tissue), presents three varieties 

 of form : 



1. The most common form consists of solid fibres of a yellowish 

 color, bifurcating or even trifurcating, and anastomosing very freely ; 

 curled or coiled up at their extremities, and sometimes being coiled 

 around other tissues. These fibres vary from 35-^^ to Wuu ^ an 

 inch in diameter, and are often studded with nuclei. More or less 

 of them are always found in connection with the white fibrous tis- 

 sue. (Fig. 170, A.) 



2. Another form found by Queckett in the ligamentum nuchae of 

 the giraffe, consists of similar coiling and bifurcating fibres, each 



1 Tinea favosa, tonsurans, decalvans, and sycosa. See Am. Med. Monthly, March, 

 1854, p. 240. 



