-
Dorsetensia is from the
middle Bajocian Humphriesianum Zone and has a
narrow fastigate (pitched roof) venter. Sepkoski, Jack (2002). "A
compendium of fossil...
-
disappear on
outer whorls leaving fine
sharp ribs.
Sharper ribs, a more
fastigate (gable roof) venter, and much
closer siphonal tubercles help distinguish...
- widely.
Below is a
partial list of cultivars: 'Armstrong' –
Columnar to
fastigate in
shape with
silvery bark and
modest orange to red fall foliage. 'Autumn...
- is involute, very compressed, with a
sharp umbilical angle and
sharp fastigate venter.
Spath (1928)speculated that
Petitclercia is
perhaps "an involute...
- They were
small and
mostly less than 2 cm in diameter.
Venter is smooth,
fastigate or rounded.
There was
constriction on aperture.
Ornamentation was weak...
-
genus had
small s**** with
semicircular whorl section and
rounded or
fastigate venter, of
which umbilicus made
about 25% of diameter. Last
whorl could...
- have
tubercles on the
shoulders and
umbilical edge, and a more or less
fastigate cross section (venter
sloping on
either side like a
gable roof), included...
- They were
small and
mostly less than 2 cm in diameter.
Venter is smooth,
fastigate or rounded.
There was
constriction on aperture.
Ornamentation was weak...
- most
members of the superfamily. Many
possess ventral chevrons and/or a
fastigate venter resembling a
gable roof,
which in some
develops into a true keel...
-
which become shortly divided near apex, in
contrast to N.
homalea with
fastigate branches that
often have
terminally divided branches of
unequal length...
