. Studies in fossil botany . Paleobotany. 25° STUDIES IN FOSSIL BOTANY the origin of the latter could not have been endogenous. Probably the rootlets were formed excessively near the apex of the parent organ. We have now to describe the characteristic structure of the fre'e rootlet, but may first point out how the anatomy of its base exactly accounts for the configura- tion of the scars on the ordinary Stigmarian surface. Fig. ioi.—Stigmariaficoides. Transverse section of rootlet, in usual state of preservation. , outer cortex ; , inner cortex ; x, xylem. x 16. S. Coll. rr3. (G. T. G.) (
. Studies in fossil botany . Paleobotany. 25° STUDIES IN FOSSIL BOTANY the origin of the latter could not have been endogenous. Probably the rootlets were formed excessively near the apex of the parent organ. We have now to describe the characteristic structure of the fre'e rootlet, but may first point out how the anatomy of its base exactly accounts for the configura- tion of the scars on the ordinary Stigmarian surface. Fig. ioi.—Stigmariaficoides. Transverse section of rootlet, in usual state of preservation. , outer cortex ; , inner cortex ; x, xylem. x 16. S. Coll. rr3. (G. T. G.) (compare Fig. 97 with Fig. 101). The outer cortex answers to the raised external rim of the scar ; the lacunar middle zone to its depressed surface ; the inner cortex to the internal circle of the scar; and the vascular strand itself to the minute central point seen in the latter, when especially well preserved. The rootlets of are absolutely the commonest specimens among the petrified material of. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Scott, Dukinfield Henry, 1854-1934. London, A. and C. Black
Size: 1540px × 1622px
Photo credit: © The Book Worm / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, bookpublisherlondonaandcblack
