According to O.M.B. Bulman (1970), the Dendroidea are sessile graptolites, "attached by apex of sicula, which is the generally more or less embedded in secondary cortical tissue forming a rootlike base, or more rarely attached by a nema; stipes composed of stolothecae, autothecae, and bithicae produced by regular triad budding; rhabdosome typically erect, dendroid in habit of growth, developed by dichotomaus or irregular branching, with anastomosis or dissepimental connection between adjacent stipes in many forms; pendent to horizontal (very rarely riclined) in forms with nema attachment."
Middle Cambrian - Carboniferous, ?Permian. |
