hand and
aphids, coccids and the like on the other; these species being sought
and attended by the ants for their own benefit: see myrmecophily.

Xenobiosis, is where one species of ant lives as a guest
in the nest of another, maintaining its own household, and mingling
freely with the host species, the two living on terms of
mutual toleration.

Symbiotic: species that live together in a state of symbiosis.

Symmetrical: evenly developed on both sides.

Symmetry: that regular arrangement of organs or parts which is
capable of division into similar halves or similar radii.

Sympathetic nervous system: applied to the nerves and ganglia of the
alimentary canal and sonic other viscera which they innervate; =
vagus; visceral nervous system.

Symphily: the relation borne to ants by the true guests which inhabit
their nests and are fed and tended: rendering in return some
substance or service desired by the ants: see metochy and synechtry.

Symphyla: a group name for apterous species resembling myriapods
in appearance, with functional abdominal legs and the genital
openings on the last abdominal segment: regarded by some as
connecting forms between insects and myriapods, e.g.
Scolopendrella.

Symphysis: where two sclerites are joined together by a soft
membrane, permitting a slight motion.

Synaptera: originally wingless insects without metamorphosis; the
Thysanura.

Synarthrosis: an articulation without motion.

Syncerebrum: the compound brain of insects.

Synchronous: happening at the same time.

Synciput: that portion of the vertex lying between the eyes.

Syncitium: masses of protoplasm with nuclei, found in ovarian tubes;
giving rise to ova, nutritive cells or both.

Syndesis: that method of articulation where two parts are connected
by a membrane which permits of considerable motion between them.

Synechtry: the relation borne to ants by insects inhabiting their nests
in spite of the efforts of the ants to destroy them: see symphily and
metochy.

Synista or Synistata: those Neuropterous insects in which the mouth
structures are undeveloped, forming an imperfect tubular structure:
see elinguata.

Synoecy: the relation that exists between ants and those guests that
are indifferent to and tolerated by them:= metochy, and see symphily
and synecthry.

Synonym: a name applied to a species or genus that has been
previously named and described.

Synonymous: words of different derivation applied t