-
found in mid
Silurian sediments in Europe. The s**** is a
longiconic cyrtocone, like that of
Jovellania or Mixosiphonoceras,
except for
being compressed...
- the Poterioceratidae, a
family of
subcircular to
compressed exogastric cyrtocones without a
hyponomic sinus.
Mecynoceras has a compressed,
gibbous cyrtoconic...
-
generally characteristic of its family, the Paraphragmitidae, an
annulated cyrtocone. In the case of
Calocyrtoceras striated both
transversely and longitudinally...
-
nautiloid cephalopods from the
Ordovician comprising exogastric longiconic cyrtocones, that is no
longer in
common use. The
Order B****lerocerida was established...
-
characterized by
depressed (or
rarely compressed)
exogastric brevicones and
cyrtocones (Sweet, 1964 K398) that
range from the
Middle Silurian to the
Middle Devonian...
- Quebec. The s**** of
Gaspocyrtoceras is a co****ly
annularted exogastric cyrtocone.
Curvature is upward, the
ventral side
convex in profile. Annulations...
-
Pseudactinoceratidae (Sweet, 1964).
Pseudactinocras are
slightly depressed longiconic cyrtocones with a
large siphuncle located between the
center and
ventral margin....
- conch, of
Cyrtocycloceras is a
moderately expanding annulated exogastric cyrtocone, with
curvature like that of a
rocking chair rocker. Annulations, encircling...
-
include gyrocones, serpenticones, torticones, and
elongate orthocones and
cyrtocones,
reflective of the
different families and
genera (Flower, 1950; Sweet...
- in Nova
Scotia and Quebec. S**** are depressed,
irregularly annulated cyrtocones with V-shaped
hyponomic sinuses,
ornamented by
longitudinal and transverse...
