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Plate II.
COCCIDIA
EB1911 Coccidia, Fig. 5.—SCHIZOGONY OF ADELEA OVATA.jpg
Fig. 5.—SCHIZOGONY OF ADELEA OVATA, A. SCHN. (PAR. LITHOBIUS FORFICATUS).
a-c, ♀ generation; d-f, ♂ generation. a, Full-grown ♀ schizont (megaschizont), with a large nucleus (n) containing a conspicuous karyosome (ky). b, Commencement of schizogony; the nucleus has divided up to form a number of daughter-nuclei (d.n). The karyosome of stage a has broken up into a great number of daughter-karyosomes, each of which forms at first the centre of one of the star-shaped daughter-nuclei; but in a short time the daughter-karyosomes become inconspicuous. c, Completion of schizogony; the ♀ schizont has broken up into a number of megamerozoites (♀ mz) implanted on a small quantity of residual protoplasm (r.p.). Each ♀ merozoite has a chromatic nucleus (n) without a karyosome. d, Full-grown ♂ schizont (microschizont), with nucleus (n), karyosome (ky), and a number of characteristic pigment-granules (p.gr). e, Commencement of schizogony. The nucleus is dividing up into a number of daughter-nuclei (d.n), each with a conspicuous karyosome (ky). f, Completion of schizogony. The numerous micro-merozoites (♂ mz) have each a nucleus with a conspicuous karyosome (ky) at one pole, and the protoplasm contains pigment-granules (p.gr) near the nucleus, on the side farthest from the karyosome. (From Minchin, after Siedlecki.)


EB1911 Coccidia, Fig. 6.—ASSOCIATION AND CONJUGATION IN ADELEA OVATA.jpg
Fig. 6.—ASSOCIATION AND CONJUGATION IN ADELEA OVATA.
a, Young microgametocyte (♂ gamc.) attached to a megagametocyte (♀ gamc.). The nucleus of the microgametocyte gives rise to 4 daughter-nuclei (c) which become (d) 4 microgametes (♀ gam.). e, One of the microgametes penetrates the megagamete, which forms a fertilization-spindle composed of male and female chromatin (♂ and ♀ chr.). The other 3 microgametes and the residual protoplasm of the microgametocyte (r.p.) perish. The karyosome of the megagamete has disappeared, as such. f, Union of the chromatin of both elements, to produce the zygote-nucleus (n.zyg.). (From Minchin, after Siedlecki.)


EB1911 Coccidia, Fig. 7.—SPORES OF VARIOUS COCCIDIAN GENERA.jpg
Fig. 7.—SPORES OF VARIOUS COCCIDIAN GENERA.
a, Minchinia chitonis (E.R.L.), (par. (Chiton); b, Diaspora hydatidea, Léger (par. Polydesmus); c, Echinospora labbei, Léger (par. Lithobius mutabilis); d, Goussia motellae, Labbé; e, Diplospora (Hyaloklossia), lieberkuhni (Labbé), (par. Rana esculenta); f, Crystallospora crystalloides (Thél.), (par. Motella tricirrata). (From Minchin; b and c after Léger, the others after Labbé.)


EB1911 Coccidia, Fig. 8.—SPOROGONY AND SPORE-GERMINATION IN BARROUSSIA ORNATA.jpg
Fig. 8.—SPOROGONY AND SPORE-GERMINATION IN BARROUSSIA ORNATA, A. SCH., FROM THE GUT OF NEPA CINERA.
a, Oocyst with sporoblasts; b, oocyst with ripe spores; c, a spore highly magnified, showing the single sporozoite bent on itself; d, the spore has split along its outer coat or epispore, but the sporozoite is still enclosed in the endospore; e, the sporozoite, freed from the endospore, is emerging; f, the sporozoite has straightened itself out and is freed from its envelopes. (From Wasielewski, after A. Schneider.)