A. _Sigillaria elegans_ Brongn. (Section in Dr Kidston’s Collection cut from the specimen shown in fig. 193, D.) B, C. _Sigillaria elongata_ Brongn. _lt_, leaf-trace. (From specimens in the collection of Prof. Bertrand.)] The large parichnos-strands, produced as in _Lepidodendron_, by the forking of a single strand arising in the middle cortical region, consist in part of tissue containing secretory canals, a structure like that recently described by Miss Coward[524] in the large parichnos strands of _Syringodendron_ stems. An example of a decorticated specimen is described by Renault[525] as _Sigillaria xylina_. This stem is presumably referred to _Sigillaria_ because the primary xylem consists of separate strands. It is characterised by the unusually large development of secondary wood and by the relatively small size of the pith. The xylem cylinder has a diameter of 4–5 cm. and the pith is only 4–5 mm. in breadth. Another example of a petrified Sigillaria stem has been described by Kidston[526] as _S. elegans_ Brongn.[527] (fig. 193, D), a species characterised by vertical rows of sub-hexagonal and contiguous leaf-scars and by the presence of verticils of cone-scars. Fig. 193, D, represents Kidston’s specimen in surface-view; one row of leaf-scars is shown, but most of the superficial tissues have been destroyed. The crushed stele, 13 mm. in its longest diameter, has a continuous cylinder of primary xylem, (fig. 202, A, _x_) characterised by a regularly crenulate outer margin with the smallest elements at the edge; the prominent ridges separating the sinuses are rounded. The leaf-traces arise from the bottom of each sinus; the leaf-bundles are mesarch, and consist exclusively of primary elements. The secondary xylem, _x²_, like that of the primary xylem, has a crenulate outer edge. The most interesting feature of the outer cortex is afforded by a tangential section which, in addition to the leaf-scars, cuts through a cone-scar showing a solid primary stele surrounded by the cortex of the cone-peduncle. Another type of _Sigillaria_, probably _S. elongata_ Brongn. (fig. 202, B, C), which is very similar to _S. scutellata_ has been briefly described by Prof. Bertrand[528], to whom my thanks are due for the two photographs reproduced in fig. 202, B., C. His specimen, from the Pas de Calais Coal-field, shows a ribbed Rhytidolepis form of surface (fig. 202, B). The stele (fig. 202, C) agrees closely with that of _S. elegans_ as described by Kidston, but the ridges on the fluted surface of the primary xylem are more pointed. “In the immediate neighbourhood of the origin of a leaf-trace, the spiral elements form a median band in the middle of a sinus” and from this the leaf-traces are given off. No secondary xylem was found in the leaf-traces at any part of their course.