This form, described by Miss de Fraine as _Sutcliffia insignis_[412], is represented by a stem rather smaller than the type-specimen described by Scott, though it is probably an older example of the same species. It is distinguished by a greater development of secondary xylem and phloem both on the main stele and the meristeles; it differs also in the absence of the greater part of the cortex and leaf-bases which have been cut off as the result of the formation of a deep-seated periderm (fig. 439, D, C). The meristeles are smaller and fewer than in the larger form and are distinguished by some other peculiarities. At _m′_ in fig. 439, D, a meristele is seen attached to the main stele. In _Sutcliffia insignis forma α_ the main stele is enclosed by an irregular network of subsidiary steles or meristeles and these form the points of departure of the leaf-traces, but the meristeles are not completely used up in the process of conversion into leaf-traces. In _Sutcliffia insignis forma β_ the meristeles agree in structure with the main stele except in the smaller amount of secondary tissue: they do not, however, form a network as in _forma α_ but occur as strands parallel to the central stele, ‘giving off leaf-traces and ultimately dividing up into smaller strands, often unequal in size, the primary wood of the meristeles being entirely used up in the production of radially symmetrical or unilateral bundles.’ In this respect, as Miss de Fraine points out, _forma β_ agrees more closely than _forma α_ with _Medullosa anglica_ and supports Scott’s view that _Sutcliffia_ is a primitive type of Medullosan stem. The leaves were given off at fairly long intervals as in some species of _Medullosa_: the leaf-traces are exarch and similar to those of the type-species. The most striking feature of the new stem is the presence of a vascular network (fig. 439, D, _e_) which encloses both the main steles and the meristeles; it consists of extrafascicular strands composed of normally orientated bands of secondary xylem and phloem often assuming a fan-like arrangement and occasionally almost concentric or inversely orientated. These strands are always accompanied by short, usually reticulate, tracheids on the inner margin of the xylem: similar isodiametric tracheids also occur in the pericyclic region. The extrafascicular strands are believed to be secondary structures phylogenetically independent of the meristeles and main stele, comparable with the successive cylinders or arcs of secondary xylem and phloem in some recent Cycads and in some species of _Medullosa_[413].