. Morphology of gymnosperms. Gymnosperms; Plant morphology. 41 '*3 42 Figs. 41-43.—Aneimites jertilis: fig. 41, fragment of pinna with seed {s); fig. 42, seed on long pedicel connected with foliage; fig. 43, seed showing wings, the latter somewhat exaggerated; X2. — After White (49). development, are associated with Aneimites in most of the deposits observed (Lower Pottsville of the Virginia region), and have been found in organic connection with the fronds of two species. They seem to represent a very different type of seed (platysperms) from those found in connection with Lyginodendron and M
. Morphology of gymnosperms. Gymnosperms; Plant morphology. 41 '*3 42 Figs. 41-43.—Aneimites jertilis: fig. 41, fragment of pinna with seed {s); fig. 42, seed on long pedicel connected with foliage; fig. 43, seed showing wings, the latter somewhat exaggerated; X2. — After White (49). development, are associated with Aneimites in most of the deposits observed (Lower Pottsville of the Virginia region), and have been found in organic connection with the fronds of two species. They seem to represent a very different type of seed (platysperms) from those found in connection with Lyginodendron and Medullosa. Pecopteris. — In 1905 Grand 'EuRY (52) announced the discovery of seeds on P. Pluckenetii. A mass of sterile and fertile pinnules was found, the latter bearing hundreds of seeds. These are not borne at the extremities of naked branchlets, the seed-bearing pinnules being very slightly modified and bearing a seed hanging freely at the extremity of the principal veinlet of each lobe (fig. 44). Scott (58) speaks of this as " the most striking instance of a 'seed-bearing fern' yet brought to ; The seeds are small (about 5 mm. long), oval, and with narrow wings. The winged habit of these seeds and of the seeds of Aneimites suggests the seeds of Cordaitales, and it becomes evident that fossil seeds can no longer be assigned with certainty except on evidence of organic connection. The discovery that a species of Pecopteris was a seed-bearing plant was one of very great interest, for it was the last great frond genus to join the Cycadofilicales, and it is the most con- spicuous genus in the variety of sporangia it bears. Probable seeds of Cycadofilicales.— In the preceding cases the evidence of the seed-bearing habit is direct and convincing; but in addition there is a possible range of inferences that are worth considering. Grand 'Eury (53) has called attention to the great. Fig. 44. — Pecopteris Pluckenetii: portion of fer- tile pinna with seeds at-
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