the upper
left border of the peristome, which is marked by a row of large
cilia. The peristome begins upon the right side of the anterior end
and passes backward and to the left, narrowing at this point. The
mouth is very small and difficult to see. It is apt to stay in
one locality under zoogloea, switching back and forth with great
vivacity, or hanging on by the posterior cilia while the anterior
end stretches out in the surrounding medium. Nucleus and contractile
vacuole were not observed. Length 45 mu.

[Illustration: Fig. 50.--_Epiclintes radiosa_.]

Genus AMPHISIA Sterki '78.

(Sterki '78; Kent '81; Buetschli '88.)

The body is plastic and soft, colorless or slightly tinged with
yellow or red. In form it is oval or elongate, the posterior end
is rounded and slightly reduced in diameter, but does not form a
distinct tail. The anterior end is also rounded and similarly reduced
in width. There are two rows of marginal cirri (_Randcirren_), which
may be placed some distance from the edge, and two or three rows of
ventral cirri between them. There are from 3 to 5 frontal cirri of
larger size than those of the ventral rows, and from 5 to 10 anal
cirri. (The genus _Holosticha_ is similar in all respects save
the presence of frontal cirri.) The macronucleus is double; the
contractile vacuole is central and on the left side. The peristome
is long and rather narrow and carries an undulating membrane on its
right margin. Fresh and salt water.

Amphisia kessleri Wrzes. '77. Fig. 51.

Synonyms: _Trichoda gibba_ Mueller; _Oxytricha gibba_ Stein '59; _O.
velox?_ Quen. '69; _O. kessleri_ Wrzes. '77.

Body elongate, slightly sigmoid and swollen in the center, about
3-1/2 times as long as broad; the rounded anterior end is turned to
the left, the similarly rounded posterior end to the right; both ends
taper slightly. The peristome is long and narrow, with a distinct
adoral zone which appears broken in its course. To the right of this
adoral zone is a single line of preoral cilia. On the right border of
the peristome is an undulating membrane. The three frontal cirri form
a triangle and the five smaller anal cirri form a continuous line
with the broken row of ventral cirri. There are two and one-half rows
of ventral cirri and the marginal cirri are drawn in until they are
ventral in position.

Length 135 mu; greatest width 40 mu.

[Illustration: Fig. 51.--_Amphisia kessleri_.]

This variety differs from _O.