- stamens,
numerous free
carpels in a
single whorl, each with 1 ovule, and
subventral styles. The
fruit is an
achene with a
short beak. The
nineteenth century...
- The
aperture is
without a
hyponomic sinus. The
siphuncle is
small and
subventral.
Other Devonian Acleistoceratidae are Acleistoceras, Paracleistoceras...
-
possessing short outer labial setae; its
short pharynx;
carrying anterior subventral teeth and a
posterior dorsal tooth in the same
stomal chamber; having...
- of the
buccal capsule. It also has a pair of
subdorsal and a pair of
subventral teeth located close to the rear.
Males are
usually 7–9 mm long, whereas...
-
elliptical transverse aperture,
without a
hyponomic sinus, and a small,
subventral siphuncle. The
phragmocone is
rapidly expanding and
strongly exogastric...
- sinuous;
siphuncle large,
subventral,
apparently orthochoantitic[clarification needed] with
tubular segments. The tubular,
subventral siphuncle separates Chidleyenoceras...
-
endogastric with the
ventral side
somewhat concave in profile. The
siphuncle is
subventral, empty, with
segments expanded into the
short but
broad chambers. Septa...
-
lower Devonian of Europe,
primarily in
having a
central rather than a
subventral siphuncle, as in Jovellania. Sweet, W. C. 1964. Nautiloidea- Orthocerida...
- large, 1/3 to 1/2 the s**** diameter;
ventral at the beginning,
becoming subventral in the
adult portion.
Septal necks are
holochoanitic to
slightly maxichaonitic...
-
large lips, each with 2 papillai,
amphidial pore at
lateral edge of each
subventral lip. Its lip
support is
lightly sclerotized.
Cervical papillae slightly...
