Some Problems of Reproduction: a Comparative Study of ...

6 MARCUS M. HARTOG.
MEMOIRS—
"Sur la Multiplication des Infusoires cilies," Maupas, in 'Arch, de
Zool. Exp.,' 1888.
"Le Rajeunissement karyogamique chez les Cili6s,' Maupas, in 'Arch.
de Zool. Exp.,' 1889.
" Karyokinesis and Fertilisation," Part II, Waldeyer (Engl. Trans.),
in ' Quart. Journ. Micr. Sci.,' Dec, 1889.
" Vergleicli der Ei- und Samenbilduug bei Nematoden," 0. Hertwig, in
'Arch. f. mikr. Anat.,' vol. xxxvi, 1890.
In my terminology I have used the word gamete to designate
a cell which fuses with another, cytoplast with cytoplast and
nucleus with nucleus, and zy gote for the cell produced by their
union; pronucleus and gametonucleus, indifferently, to
denote the nucleus of a gamete, without any connotation of
imperfection; gametogonium and progamete to express,
from slightly different points of view, a cell which divides to
form gametes or (rarely) passes into the state of a gamete;
spermatogonium 1 and oogonium, spermatogamete and
oogamete for male or female gametogonia and gametes
respectively: facultative and obligatory gametes are discriminated
according as they retain the primitive cell privilege
of multiplying by fission (independent of karyogamy) or
have lost it altogether. I use the phrase gametangium for
the apocytial chamber in which gametes are developed. Cytoplast
designates the cytoplasm considered as a unit in contrast
to the nucleus.
By apocytium I mean a mass of protoplasm which is
habitually plurinucleate, cell division remaining in abeyance;
apocytial plants may be continuous; or septate by
partitions, which always, however, separate multinucleate
masses of protoplasm. Apocytial structures which unite
like gametes are termed gametoids, and the product of
their union a zygotoid. I have freely used Maupas's admirable
term karyogamy to comprise all forms of union of
gametes involving fusion of their nuclei, since fertilisation
and fecundation are altogether inappropriate to cases of
1
Corresponding with the " spermatospore " of Blomfield, not necessarily
the " spermatogonium " of La Valette St. George.