A treatise on physiology and hygiene for educational institutions and general readers .. . climates. It is also well illus-trated by the fact, that amongthe Jews who have settled innorthern Europe, there are manywho are fair-complexioned, whilethose residing in India are as darkas the Hindoos around them. 11. An Albino is a person whomay be said to have no com-plexion; that is, there is an en-tire absence of coloring matterfrom the skin, hair, and iris ofthe eye. This condition existsfrom birth, and more frequentlyoccurs among the dark races, andin hot climates, although it hasbeen observed in
A treatise on physiology and hygiene for educational institutions and general readers .. . climates. It is also well illus-trated by the fact, that amongthe Jews who have settled innorthern Europe, there are manywho are fair-complexioned, whilethose residing in India are as darkas the Hindoos around them. 11. An Albino is a person whomay be said to have no com-plexion; that is, there is an en-tire absence of coloring matterfrom the skin, hair, and iris ofthe eye. This condition existsfrom birth, and more frequentlyoccurs among the dark races, andin hot climates, although it hasbeen observed in almost everyrace and clime. 12. Sebaceous Glands.—In all parts of the surface where thehairs grow, are to be found the sebaceous, or oil-producing glands are little rounded sacs, usually connected with the hair-bulbs ; and upon these bulbs they empty their product of oil, whichacts as a natural dressing for the hair (4, Fig. 17). A portion ofthe sebaceous matter passes out upon the surface, and prevents thecuticle from becoming dry and hard. The glands situated upon the. Fig. 18.—Showing a Hair and Section ofSkin highly magnified. 9. On what does the complexion depend ? Light and dark races ? Freckles ? 10. Influence of the sun? How illustrated? Jews? 11. What is an Albino? Where areAlbinos found? 12. What are sebaceous glands ? How do they act ? Sebaceous glands of the face ? Howdo they act ? THE INTEGUMENT, OR SKIN. 53 face and forehead open directly upon the skin. In these, the seba-ceous matter is liable to collect, and become too hard to flow offnaturally. 13. These glands on the face and forehead frequently appear onthe faces of the young as small, black points, which are incorrectlycalled worms. It is true, that occasionally living animalculesare found in this thickened sebaceous matter, but they can only bedetected by the aid of the microscope. This sebaceous matter actsnot only to keep the skin flexible, and furnish for the hair an oilydressing, but i
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Keywords: ., bookcentury1800, bookdecade1, booksubjectphysiology, bookyear1884
