. The biology of the protozoa. Protozoa; Protozoa. 238 BIOLOGY OF THE PROTOZOA formation of specialized structures of the fruiting bodies (elaters, etc., Kranzlin, 1907); others divide by mitosis to form nuclei of the spores contained with the elaters in the spaces of a meshwork formed by a special protective and supporting part of the fruiting bodies called the capillitium (Fig. 184, p. 447, see also p. 44(i). Multiple division in the Sporozoa is characteristic of practically all Coccidiomorpha, particularly in agamogony. The nuclei divide repeatedly by mitosis until many are formed, after wh
. The biology of the protozoa. Protozoa; Protozoa. 238 BIOLOGY OF THE PROTOZOA formation of specialized structures of the fruiting bodies (elaters, etc., Kranzlin, 1907); others divide by mitosis to form nuclei of the spores contained with the elaters in the spaces of a meshwork formed by a special protective and supporting part of the fruiting bodies called the capillitium (Fig. 184, p. 447, see also p. 44(i). Multiple division in the Sporozoa is characteristic of practically all Coccidiomorpha, particularly in agamogony. The nuclei divide repeatedly by mitosis until many are formed, after which the body plasm breaks up into as many agametes as there are nuclei. In many cases a portion of the old cells is left unused or not included in the protoplasm of the offspring. Thus in Plasmodium vivax and other malaria organisms, the pigmented granules (melanin) are left behind when the agametes separate (Fig. 124); in many coccidia the agametes are oriented in respect to such residual products. Multiple division is also characteristic of the developing zygotes of gregarines and hemamebidae, the eight sporozoites of gregarines and the multitude of Sporozoites of Plasmodium being formed in this A B C Fig. 124. — Malaria organisms. .4, Plasmodium vivax in blood corpuscle; B, same in agamete formation with distributed melanin (m). C, Plasmodium ?nalariae, agamete formation with concentrated melanin, c, red blood corpuscle; m, melanin; n, nuclei; /), parasite; v, vacuole. (After Calkins.) In the above account of the reproductive activities of the Protozoa no attempt has been made to give an exhaustive treatment, but other examples will be given in the following chapters on classi- fication. In many cases in the above description there is evidence of reorganization of the protoplasm and evidence that may be inter- preted as supporting Child's view of de-differentiation as an offset to the accumulation of products of metabolism which hamper further metabolic activities
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