EXPLANATION OF THE PLATES OF TRIPLOSPORITE.
Tab. 34 (XXIII).
The figures A, B, C, and D are of the natural size.
Fig. A. A portion of the surface of the Strobilus, showing the hexagonal areolæ.
Figs. B & C. Transverse seetions, exhibiting different appearances of the bracteæ and sporangia.
Fig. D. A vertical section of fig. A.
The remaining figures, E, F, G and II, are all more or less magnified.
Fig. E. A transverse section of the axis.
Fig. F. A more highly magnified drawing of a portion of fig. E, to show the arrangement and proportion of the vascular and cellular tissues.
Fig. G. A horizontal section of a sporangium, made probably near its origin.
Fig. H. A portion of the outer wall of a sporangium or bractea.
Tab. 35 (XXIV).
All the figures magnified.
Fig. A. A vertical section of the axis, near, but not exactly in the centre, showing the ramifications of the central cord of the axis going to the circumference of the axis, and connected or supported by a loose cellular tissue at a a.
Fig. B. A small portion of the axis, from which proceeds a bractea cut vertically through its centre, showing its vascular cord, and bearing on its lower and horizontal half a vertical section of an adnate sporangium, of which the base is cellular, rising irregularly and without spores,—probably a rare occurrence.
Fig. C. A small portion of the axis, to show the scalariform vessels with [475 the slightly elongated surrounding cells.
Fig. D. A similar portion, from the central axis of the bractea of fig. B.
Fig. E. A similar portion, from the line of union between the bractea and sporangium of fig. B.
Fig. F. A small portion of a sporangium, sufficiently magnified to show the arrangement and composition of sporules.
Fig. G. Several sporules, both in their compound and simple state, still more highly magnified, with the minute granular matter which usually accompanies them.
