. Pathogenic micro-organisms, including bacteria and Protozoa; a practical manual for students, physicians and health officers. cfor this species, and is not seen, according to Schaudinn, in any otherintestinal parasites. In the beginning of the large intestine of the new host the cystwall is dissolved, the cyst contents divides into eight young amebae(sporogony), and the cycle begins anew. The permanent cysts of Ent. histolytica, on the contrary are formed inan entirely different manner. The nucleus of the ameboid form en-larges, the chromatin increases, and most of it passes out as chromidia
. Pathogenic micro-organisms, including bacteria and Protozoa; a practical manual for students, physicians and health officers. cfor this species, and is not seen, according to Schaudinn, in any otherintestinal parasites. In the beginning of the large intestine of the new host the cystwall is dissolved, the cyst contents divides into eight young amebae(sporogony), and the cycle begins anew. The permanent cysts of Ent. histolytica, on the contrary are formed inan entirely different manner. The nucleus of the ameboid form en-larges, the chromatin increases, and most of it passes out as chromidiainto the cytoplasm which is finally filled, while the nucleus degenerates. GYMNAM(EBIDA. 541 On the surface of the cytoplasm are now formed small rounded bodiesof 3 to 7/i diameter. These balls, which can be seen forming in thehanging drop, produce about themselves a double-contoured membranewhich after several hours takes a clear brownish-yellow color, and l)e-comes very refractive. At this stage no structure can be made out withinthe ball. The rest of the ameba finally degenerates. The stained prep- FiG. 167 ^^chizogon3. Scheme of the flevelopment cycle of Enlamcehii coii (Losch). 1-5 Schizogony of the vegetativeform, .i and 4 nuclear increase through multiple nuclear division, .5 cell division, 3a division intotwo of the vegetative forms; 6-12 autogamy within the cyst, 7 first nuclear division, 8 incom-plete cejl division and chromidium forming, 9 formation of the gamete nuclei from the sexualchromidiurn, 10 formation of two reduction nuclei, 11 division of the reduced gamete nuclei inmotile nuclei (male) and stationary nuclei (female), 12 both the syncaria after fusing of the motileand stationary nuclei, i:-! and 14 sporogeny within the cyst, 13 cystwith S nuclei; produced by sue-cessjve mitoses from the two syncaria, 14 bursting of the cyst and freeing of the S young amelup inthe intestines of a new host. After Hartmann, from >Schaudinns description (from Kisskalt andHa
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