Fig. 7 in The ultrastructure and building of graptolite dissepiments

Fig. 7. Dendroid graptolite "Dictyonema" sp. 2, TEM micrographs. A. Ordovician boulder No. O.62. Longitudinal section through the expanded base of a dissepiment showing delicate fusellar fabric filling the first conical growth bands and producing the fusellar core enveloped by a heavy cortical deposit. B. Laminar growth bands with cortical content.