. Morphology of gymnosperms. Gymnosperms; Plant morphology. cycadofiliCales 31. Fig. 25.—Lagenostoma Lomaxii (restored): the seed is surrounded by a glandular cupula.—After Oliver and Scott (48). THE MEGASPORANGIUM Numerous detached paleozoic seeds have been discovered, but it must be remembered that they include the seeds of both Cordaitales and Cycadofilicales. The seeds defi- nitely connected with Cycadofilicales » "^ '^ are comparatively very few, but the structure of at least two of them is known with remarkable completeness. —In 1903 Oliver and Scott (39) announced that
. Morphology of gymnosperms. Gymnosperms; Plant morphology. cycadofiliCales 31. Fig. 25.—Lagenostoma Lomaxii (restored): the seed is surrounded by a glandular cupula.—After Oliver and Scott (48). THE MEGASPORANGIUM Numerous detached paleozoic seeds have been discovered, but it must be remembered that they include the seeds of both Cordaitales and Cycadofilicales. The seeds defi- nitely connected with Cycadofilicales » "^ '^ are comparatively very few, but the structure of at least two of them is known with remarkable completeness. —In 1903 Oliver and Scott (39) announced that a species of this seed genus is the seed of Lyginodendron Oldhamium, and in the following year the full account appeared (48). The seed species was a new one, and was described as Lage- nostoma Lomaxii (fig. 25). The seeds were not found in actual organic con- nection with the foliage (Sphenopteris) of Lyginodendron, but the numerous and peculiar capitate glands borne on the cupule correspond in every detail to those on the vegetative organs of the associated Lyginodendron, and represent a character not possessed by any other associated plant. There seemed to be no doubt that the reference of the seed to Lygino- dendron was fully justified, a conclusion further confirmed by a comparison of the anatomical details. Another species of Lagenostoma (L. ovoides) was known; and later Arber (51) described L. Kids- tonii and L. Sinclairii from casts, but important in that the seeds were con- nected with branching axes that represent naked branches of a frond (fig. 26). It is evident, therefore, that the leaves of Lyginodendron were dimorphic, one form being the familiar sterile fohage of the Sphenopteris 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 Coulter, John Merle, 1851-1928; Chamberlain, Charle
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