. Fossil plants : for students of botany and geology . Paleobotany. 464 COENOPTERIDEAE [CH. sporangium has a pedicel, and three to eight sporangia are attached to a common peduncle; the walls of the sporangia are at least two cell-layers in thickness and the annulus consists of a band of thick-walled cells passing from the crest down each side (figs. B and C), thus differing from the sporangia of Botryo- pteris (fig. 319, D, F) in which the broad annulus is confined to one side. It is practically certain that the fronds described by Grand'Eury* as Schizopteris pinnata (fig. 309, E) and Schizo-
. Fossil plants : for students of botany and geology . Paleobotany. 464 COENOPTERIDEAE [CH. sporangium has a pedicel, and three to eight sporangia are attached to a common peduncle; the walls of the sporangia are at least two cell-layers in thickness and the annulus consists of a band of thick-walled cells passing from the crest down each side (figs. B and C), thus differing from the sporangia of Botryo- pteris (fig. 319, D, F) in which the broad annulus is confined to one side. It is practically certain that the fronds described by Grand'Eury* as Schizopteris pinnata (fig. 309, E) and Schizo- stachys frondosus represent respectively the sterile and fertile. Fig. 320. Stauropteris oldhamia. (After Tansley. From a aeotion in Db Scott's Collection, x 60.) leaves of Etapteris. Zeiller'' gives expression to this by substi- tuting the generic name Zygopteris for Schizopteris, and we may now speak of the leaves as Etapteris. Dr White' has referred to a new genus, Brittsia, some impressions of pinnate fronds from the Coal-Measures of Missouri which, as he points out, bear a close resemblance to Schizopteris pinnata Grand'Eury (fig. 309, E). No sporangia have been found; it is, however, probable that Brittsia problematica represents fragments of a 1 Grand'Eury (77) A. PI. xvii. 2 Renault and ZeiUer (88) A. » White (99) p. 97. ^ '. 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 Seward, A. C. (Albert Charles), 1863-1941. Cambridge : University Press
Size: 1901px × 1315px
Photo credit: © Central Historic Books / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, bookpublishercambr, bookyear1898
