Parasitology, Harold W. Manter Laboratory of


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Journal of Experimental Medicine (1902) 6(3): 303-316

doi: 10.1084/jem.6.3.303

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In 1889, Smith published a preliminary description of a polysporous coccidium found in the epithelium of the convoluted tubules of the mouse's kidney. Several stages of the parasite were seen but the scantiness of the material left many gaps in the life-cycle. During investigations recently made to determine the mode of transmission of the Sarcosporidium of the mouse, Smith found a considerable number of gray mice, caught in the animal room connected with this laboratory, whose kidneys were abundantly invaded by this coccidium. This favorable opportunity of examining more thoroughly into the life-history of this sporozoon was utilized, and, as a result, we are able to add materially to the knowledge of this cell parasite. In the following pages some details given in the first paper will be repeated to avoid obscurity in the descriptions as well as to aid those to whom the first paper is inaccessible.

Thus far we have found only adult mice infected. The invaded kidneys are a trifle enlarged and the surface is faintly uneven. The most characteristic feature is a very delicate mottling of the whole surface with minute, barely visible, grayish specks. This appearance of the kidneys may be considered almost diagnostic of the presence of the parasite.

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