University of California Publications in Zoology Volume 16
This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1917 edition. Excerpt: ...in figures 34 to 41. The same thing is found in any group of trypanosomes, as may be seen in the plates of Chagas (1909), Minchin and Thompson (1915) and others, though the variation is less in these forms than in the flagellates Trypanoplasma and Prowazekia. This might be expected from a comparison of the media in which these flagellates live, the blood forming a more nearly constant medium than does the intestinal contents with its constant fluctuations in both quantity and quality. Considering the parabasal bodies as related in their origin and development to the processes of metabolism it seems not improbable that these structures may be homologous to the mitochrondria in the metazoan celi. The parabasal bodies of the Trichonymphida are structures related to the blepharoplast, the kinetic center of the cell, and, in two cases at least, are formed by direct outgrowth from it. They are permanent cell organelles, persisting from one division cycle to the next. Janicki (1911) has described their composition as "an fixierten und gefarbten Preparaten, besonders an osmierten, als aus dichten, durchaus homogenen Plasma zusammengesetz; seine Konturen sind nicht sehr scharf ausgedriickt; eine Membran, welche das Plasma umschlosse wird nicht beobachtet." With these, as is also the case with the chromidial bodies of Prowazekia, all stains, as, for example, Delafield's haematoxylin, do not produce nuclear reactions. This proves tbat it is not composed of nuclear chromatin, or at least not of unmodified nuclear chromatin. It will be pointed out in greater detail below that the parabasal body of trypanosomes is also not composed of nuclear chromatin in the sense that it is chemically identical with the intranuclear materiai. In his latest...
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