FIG. 11.—Calamodendron, from Autun; prosenchymatous portion of the wood silicified, X200.
FIG. 12.—Calamodendron, from Autun; vascular portion of the wood silicified.
If we refer to Fig. 13, which represents a radial vertical section running through the center of one of the scars that permitted the specimen to be determined, we shall observe, in fact, a tissue formed of rectangular cells, longer than wide, arranged in horizontal series, and very analogous in their aspect to those that we have described in the suberose region of the bark of Sigillariæ. Fig. 15 shows in tangential section the fibrous aspect of this tissue, which has been rendered denser through compression. Fig. 14 shows it restored. In Fig. 13, the external part of the bark is occupied by a thick layer of cellular tissue that exists over the entire surface of the trunk, but particularly thick near the scars, exactly as in the barks of the Sigillariæ that we have formerly described. Finally, at b, we recognize the undoubted traces of a vascular bundle running to the leaves. If the bundle appears to be larger than that of the Sigillariæ, this is due to the flattening that the trunk has undergone, the effect of this having been to spread the bundle out in a vertical plane, although its greatest width in the first place was in a horizontal one.
FIG. 13.—Syringodendron pes-capræ; from Saarbruck; radial vertical section, X200.
FIG. 14.—Suberose cells restored.
In anatomical structure, the barks of the Syringodendrons are, then, analogous to those of the Sigillariæ. If, now, we compare the dimensions of the tissues of these barks with the same silicified tissues of the barks of Sigillariæ, we shall find that there was likewise a diminution in the dimensions, but yet a less pronounced one than in the woods that we have previously spoken of. The corky nature of this region of the bark was likely richer in carbonizable elements than the wood properly so called, and had, in consequence, to undergo much less shrinkage.—Dr. B. Renault (of Paris Museum) in Le Genie Civil.