mber 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 [venus] schizont has broken up into a number of _megamerozoites_
([venus] mz) implanted on a small quantity of residual protoplasm
(r.p.). Each [venus] merozoite has a chromatic nucleus (n) without a
karyosome. d, Full-grown [mars] 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 ([mars] 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.)]

[Illustration: FIG. 6.--ASSOCIATION AND CONJUGATION IN _ADELEA OVATA_.

a, Young microgametocyte ([mars] gamc.) attached to a megagametocyte
([venus] gamc.). The nucleus of the microgametocyte gives rise to 4
daughter-nuclei (c) which become (d) 4 microgametes ([venus] gam.). e,
One of the microgametes penetrates the megagamete, which forms a
fertilization-spindle composed of male and female chromatin ([mars]
and [venus] 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.)]

[Illustration: FIG. 7.--SPORES OF VARIOUS COCCIDIAN GENERA.

a, _Minchinia chitonis_ (E.R.L.), (par. _Chiton_); b, _Diaspora
hydatidea_, Leger (par. _Polydesmus_); c, _Echinospora labbei_, Leger
(par. _Lithobius mutabilis_); d, _Goussia motellae_, Labbe; e,
_Diplospora_ (_Hyaloklossia_), _lieberkuhni_ (Labbe), (par. _Rana
esculenta_); f, _Crystallospora crystalloides_ (Thel.), (par. _Motella
tricirrata_). (From Minchin; b and c after Leger, the others after
Labbe.)]

[Illustration: 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