different form: but the spores in composition, form, and apparently in size were identical. This specimen had then very recently been received from the Strasburg Museum, but nothing was known of its origin or history.
- May 5, 1851.
EXPLANATION OF THE PLATES OF TRIPLOSPORITE.
Tab. 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. 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.
