Edwardsia andresi, dissected longitudinally. a. Septa of
the posterior portion; b. Septa farther forward, with longitudinal muscles
and mesenterial filaments; c. Gullet-tube with septal insertions.
Actinauge rugosa Longitudinal section. cp, infolded capitulum:
a, a, tentacles: e, sphincter muscle; d, f, verrucae or tubercles; o, stomodaeum;
p, wall of stomodaeum; n, its external layer; m, s, 1-4, perfect mesenteries
of 1 to 4 pairs; r, a pair of primary perfect mesenteries; g, ectoderm
of body wall; i, endoderm; n, mesogloea; c, circular muscles of body-wall;
1, 1, gonads and mesenterial filaments; b, surface of base; t, section
Actinauge borealis. Longitudinal section of the upper part
of the column; e, sphincter muscle; c, retracted capitulum; h, mesogloea;
g, ectoderm with remains of dark coating; d, invected disk; t, t', bases
of crowded tentacles; v, larger tubercles of the parapet; m, upper ends
of the mesenteries, pink in colour; o, oral region of disk.
Entire body longitudinal section of Actinia priapus.
Thelaceros rhizophorae. Inner (endocoelic) face of a mesentery
of the first order, with the adjacent exocoelic tentacle. b.w. Body wall,
thick in the column and on the base, thin on the disc. l.m. 1, l.m. 3,
l.m. 4. Longitudinal muscle. l.m. 2. Parieto-basilar muscle. st. Stomodaeum.
g. Genital organ. m.f. Contorted edge of mesentery, with filament.
Octineon lindahli. Much enlarged view of a but little compressed
specimen laid open so as to exhibit the essential internal structures (probably
a combined, more of less diagrammatic representation). The stomodaeal tube
[or rather, the inturned part of the column,] is laid open, and it is seen
that the cuticle of the outer surface of the body, with its dense coating
of sand and shell particles, is continued to its base. Here it opens into
a discoid chamber, which may be called the tentacular chamber [formed by
a folding of the oral disc], since [the pouches for] the invaginated tentacles
communicate with it all round its periphery by open mouths. [In one of
the pouches pointing directly towards the observer, which has been cut
across, the tentacle can be seen lying as in a sheath.] In the middle of
this chamber below, lies the mouth, leading into the stomach cavity [stomodaeum]
below. The latter is surrounded by the radiating retractor muscles, with
the ovaries showing beneath them, and by the [sheaths of the] tentacles
between the muscles. Six retractor muscles are shown, and eight [sheaths
for] tentacles. The directive muscles are apparently the pair on the extreme
right and those on the extreme left of the figure [as there is only one
entocoelic tentacle sheath between them.