Dictyonema
crassibasale
Dictyonema is the good example of the 2nd most abundant group of graptolites, the
dendroids. Dendroid graptolites attached to substrates and had
colonial skeletons (rhabdosomes) that are generally broadly branching (conical to
fan-shaped to shrub-like to flat spirals). They are typically
preserved as carbonized compressions parallel to bedding planes, as are graptoloid
graptolites.
Dictyonema crassibasale Gurley in Bassler, 1909 (Animalia,
Hemichordata, Graptolithina, Dendroidea, Dendrograptidae) in dolostone from the
Lockport Dolomite (upper Middle Silurian) of the Hamilton area, southeastern
Ontario, southeastern Canada. Colorado School of Mines Geology Museum
public display, Golden, Colorado, USA.