EXPLANATION OF THE PLATE. 
Fra. 1. Inner surface of split leather showing the cavities formed by the 
enlarged hair-follicles. Six or seven of these cavities are filled with the seba- 
ceous secretion. (Natural size.) 
Fig. 2, Cross-section of a piece of the untanned skin from which the hair 
has been removed, showing one of the diseased follicles filled with fat. (Natu- 
Tal size.) 
Fra. 3. Cross-section of the same. The sebaceous matter has been removed 
from the folliele, (Natural size.) 
Fia. 4. A similar section magnified, showing one of the infested follicles 
together with four in the normal state. The light-colored bodies near the 
surface of the skin are sebaceous glands, 
Fra. 5. Magnified section of a hei Ithy skin from which the hair has not 
been removed, 
Fra. 6. Demodez folliculorum from one of the infested hair-follicles, highly 
magnified (Hartnack obj. 9, oc. 4). The annuli of the abdomen are too 
Strongly marked, 
Fra. 7. Anterior part of the same, much enlarged. 
Fia. 8. Egg of ۷ 
Fra. 9. The same, in which the yolk has shrunk away from the shell. 
