In early forms the siphuncle is central or subcentral, orthochoanitic ( septal necks short and straight ), and thin, with tubular segments.
42.
Overall ellesmerocerids are characterized by moderate endogastric curvature, and a marginal siphuncle with irregular diaphragms, ellipochoanitic septal necks, and thick complex connecting rings.
43.
Siphuncle segments nummuloidal ( beaded in appearance ), septal necks cyrtochoanitic ( flared outwardly ) generally with recumbent ( bent back on themselves ) brims.
44.
Siphuncle segments are short, as are chambers; septal necks recurved, connecting rings thick, bullettes at the apical end of the rings swollen.
45.
The siphuncle is typically nummuloidal, like a string of beads, with outwardly flared septal necks, and located between the center and the venter.
46.
Siphuncle : small, slightly ventral of the center, thought to be orthochoanitic ( straight septal necks ) and cylindrical ( tubular connecting rings ).
47.
Septal necks are macrochoanitic, up to two camerae ( chambers ) long; connecting rings, one chamber in length line the inside of the necks.
48.
Septal necks are typically orthochoanitic ( short, straight ) but may slant inwardly ( loxochoanitic ) or reach halfway to the previous septum ( hemichoanitic ).
49.
The siphuncle in " Ectenolites " lies along the ventral side; is tubular, composed of short orthochoantic septal necks and thick concave connecting rings.
50.
Connecting rings are thick and uniform, each extending from the tip of a septal neck to the tip of the preceding neck . ( T & G 1954)
