Acarus folliculorum — Chambers's Encyclopaedia

Acarus folliculorum, or DEMODEX FOLLICULORUM, is a microscopic parasite allied to the mites, which inhabits the hair-follicles and sebaceous glands of the human skin, also the wax of the ear. It is found most commonly in the skin of the nose, and is present in a large proportion of healthy individuals, but is of no practical importance. It may be seen when present by squeezing out the contents of a sebaceous follicle, mixing with a little oil on a glass slide, and examining under the microscope. It is from $\frac{1}{100}$ to $\frac{1}{1000}$ inch in length. The thorax occupies from $\frac{1}{2}$ to $\frac{2}{3}$ of its length, and is furnished with four pairs of rudimentary limbs. See PARASITES.