Page:Tropical Diseases.djvu/951

XLVI] which spread rapidly; the latter including the red and white patches, apparently involving the rete and deeper layers of the epidermis, spreading more slowly, and, at the same time, being more difficult to cure. The various forms and colours may concur in the same individual; but a given patch, once established, does not change colour.

Pinta is contagious. It attacks both sexes and any age. Unless properly treated it may last for years. Pathology.— If one of the scales is moistened with liquor potassæ and placed under the microscope, black spores and a white, highly refracting mycelium are found. The spores are round or oval, measuring 8 μ to 12 μ in diameter. Abundant pigment is seen floating in a yellowish fluid in the interior of the spore. The mycelial filaments are short, non-branching, tapering from a broad base to a blunt point by which each filament is attached to a single spore, like the stalk to a cherry. The mycelium measures from 18 μ to 20 μ in length by 2 μ in breadth. The differences in the colour of the patches probably depend on differences in the pigmentation, or kind, of the fungus. Such is Gastambide's description of the parasite— a description which, to some extent, is borne out by Osborne Browne.

Montoya y Florez has published an elaborate and careful description of the disease and of the various mycotic growths he found in the several varieties of pinta which he studied. He says that he has never seen a fungus answering to Gastambide's description. On placing the scales moistened with liquor potassæ under the microscope, long dichotomous filaments, generally very fine and cylindrical, in certain conditions granular and beaded, are seen. In places this mycelium forms a dense network. Here and there veritable ropes of mycelium are visible, or broad, short filaments with fructification characteristic of the particular variety of the disease may be detected (Fig. 207), He has succeeded in cultivating the various fungi, which apparently belong to a plurality of genera— Penicillium, Aspergillus, Manilla. Diagnosis.— This disease is readily diagnosed