At the distal end the pedicel has a thin marginal wing (fig. 218, C, right-hand half) continuous with the upturned protective lamina. To the upper face of each sporophyll is attached along the whole length as far as the ligule, a single large sporangium; on each side of the base of the sporangium the sporophyll forms a supporting cushion. The relation of the sporangium to the ligule, _l_, is shown in fig. 218, B, and in the tangential section, C, which illustrates the triangular form of the sporangium near its distal end. In mature cones, the sporangia assumed the form of seeds, the change being due to the growth of an investing integument from the upper face of the sporophylls on each side of the sporangia. Fig. 218, A, illustrates the form of a sporangium as shown in tangential sections; the vascular bundle is seen below the base of the sporangium and the gaps right and left of it probably mark the position of parichnos strands. On each side of the sporangium, _b_, a fairly thick wall of tissue has grown up from the sporophyll, forming an integument which overtops the apical ridge of the sporangium, leaving a narrow micropyle in the form of a long crevice (_m_, fig. 218, B). At the proximal end of the sporangium the integument forms an enclosing wall; at the distal end it abuts on and is continuous with the upturned end of the sporophyll. It is clearly established by Scott that the tissue which invests the sporangia is not the upturned margins of the sporophyll, but a new formation fully entitled to the designation integument. It is noteworthy that the integument is not developed until a late stage in the ontogeny of the strobilus; it is not formed until after the production of the prothallus[667]. The diagrammatic sketch, fig. 218, B, shows the relation of the integument to the sporophyll and sporangium, the outline of the latter being indicated by a broken line. The columnar wall of the sporangium (fig. 218, A, _b_) forms a closed beak within the micropylar crevice, and in the interior of the sporangial cavity the slightly shrivelled membrane, _a_, represents the single megaspore; traces of the aborted sister-cells of the megaspore are occasionally met with. Scott describes a specimen in which the megaspore is filled with tissue agreeing in appearance with the prothallus in a megaspore of _Isoetes_ or _Selaginella_; no undoubted archegonia or female organs have been discovered, nor has any spore been found containing an embryo. [Illustration: FIG. 218. _Lepidocarpon Lomaxi_, Scott. A and C. After Scott. B. Diagram of a single sporophyll: _m_, micropyle; _St_, stele.] The axis of _L. Lomaxi_ has a medullated stele constructed on the same plan as that of some species of _Lepidodendron_ and _Lepidostrobus_; the vascular bundles supplying the sporophylls pass obliquely upwards and outwards from the stele, _St_, fig. 218, B, and bend slightly downward just before entering the pedicel of a sporophyll.