![]() The depth of color of the deep stratum of the epidermis of the negro is evidently due to the composition of that layer, of these granules chiefly." Pigment bearing cells are most abundant in the furrows of the derma, and in the hollows between " the papillae. separately they offer very little indication of the depth of color which is produced by their accumulation some have the hue of amber, while others scarcely exceed the most delicate fawn. The nucleus of the cell, in the epidermis of the negro, appears to consist wholly of pigment granules, while in the European there is a greater or less admixture of coloured When the granules are examined and uncoloured granules. On the amount of these granules depends the varying depth of tint of the skin in different parts of the body, in different individuals, and in different races.* They existf "accumulated round the nucleus, and dispersed les3 numerously through the rest of the cell. The pigment granules are found mostly in the lowermost layers of the rete mucosum, and the color gradually diminishes in the uppermost layers, so that it is almost imperceptible in the epidermic scales. Secondary or symptomatic stainings,?following in the wake of other diseases, or due to disturbance of organs at a distance from the seat of discoloration, or as I prefer to put it, that do not constitute the essential disease, but are secondary to, or form only a part of, the essential disease present in any given case." is seen in areĬhromatogenesis consist in variations in the amount, distribution, and occasionally color, of the pigment normally found in the rete mucosum, the formative layer of the epidermis, where it exists in the form of fine granular brownish yellow pigment corpuscles, lying in the ordinary epidermic, and not in special, cells. ![]() They include leucoderma, melanoderma, &c., not connected with, or symptomatic of, general constitutional or local diseases." " 2. The idiopathic staining3 generally localised in particular parts. Scratching also will be followed in some cases by discoloration. g., mustard plasters, or pressure on a part as by dresses, mechanical restraints, the friction of straps, and the following of certain handicrafts, by which certain parts of the body are exposed to the sun, or specially rubbed, as in masons. Of irritants, which set up hypereemia in some cases, and in others not, as after the action of heat, or friction, or irritants, e.
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