In his Monograph of Fossil Conifers Goeppert figured a large piece of stem consisting mainly of secondary wood and described the more important anatomical features. He recognised the narrow, transversely elongated, pits on the radial walls of the tracheids as a feature of special interest indicating a type of pitting transitional between that of Ferns and Conifers. A further description was given by Kraus[531] who included under Goeppert’s name both the Falkenberg stem and a second specimen from Basel though the latter is Triassic in age and a distinct plant; he suggested a comparison of _Protopitys_ with _Sigillaria_ and _Stigmaria_ rather than with Conifers. It is, however, to Graf Solms-Laubach[532] that we owe the most thorough account of this species. Nothing is known of the leaves or reproductive organs. The largest piece of stem is nearly 1 ft in diameter and consists mainly of secondary xylem resembling that of Conifers and _Cordaites_ except in the form of the bordered pits on the radial walls of the tracheids (fig. 462, D). The centre of the stem is occupied by a parenchymatous pith, elliptical in transverse section, enclosed by a band of primary xylem composed of large polygonal tracheids (fig. 462, C, _x_¹) characterised by a delicate scalariform pitting on all their walls (fig. 462, E). The primary xylem forms a narrow layer on the sides of the ellipse, 1–3 elements broad (fig. 462, A, B), but it increases in breadth at the ends of the long axis where the tracheids are intermixed with parenchyma. The primary xylem and pith-tissue at the ends of the major axis of the central region assume different forms at different levels, owing to the detachment of leaf-traces and the consequent formation of foliar gaps as portions of the primary xylem pass obliquely outwards into the secondary xylem on the way to the distichously arranged alternate leaves. The diagram, fig. 462, A, shows the inner part of the secondary xylem (see also fig. 462, C, x²) which at one end, _lt_, has formed an oval group about to pass out as a leaf-trace: at the opposite end the strand is detached and divided into two equal branches. The two swellings of the primary xylem ellipse shown at _a_ in figs. 462, A and B, are a characteristic feature: these are clearly seen after the leaf-trace has become detached; at the inner edge of each of them there appears to be a protoxylem strand. After the formation of a foliar gap these swellings of the xylem gradually meet and so re-establish continuity below the outgoing leaf-trace. No protoxylem has been detected in the actual trace, which is believed to be concentric. The formation of the leaf-gap and the shoulders bordering it constitute interesting filicinean features, recalling corresponding characters in solenostelic Ferns. At the upper end of the diagram, fig. 462, B, the outgoing leaf-trace is undergoing dichotomy while at the opposite end the trace has passed out of view.