. Fossil plants : for students of botany and geology . Paleobotany. 12 CYCADALES [CH. â palaeobotanical student of the occurrence of flowering plants with stems closely simulating those of some Cycads. Prof. Bower^ in describing Rhynchofetalum montanum, an Abyssinian Lobelia- ceous plant, drew attention to the similarity in surface-features and to some extent in anatomical structure to cycadean stems. The resemblances are further emphasised in a more recently pubhshed account of the same species under a different name, Lobelia Khyncho-petalum^. Fig. 383. Cycas siamensis. (From the Encyclopaedi
. Fossil plants : for students of botany and geology . Paleobotany. 12 CYCADALES [CH. â palaeobotanical student of the occurrence of flowering plants with stems closely simulating those of some Cycads. Prof. Bower^ in describing Rhynchofetalum montanum, an Abyssinian Lobelia- ceous plant, drew attention to the similarity in surface-features and to some extent in anatomical structure to cycadean stems. The resemblances are further emphasised in a more recently pubhshed account of the same species under a different name, Lobelia Khyncho-petalum^. Fig. 383. Cycas siamensis. (From the Encyclopaedia Britannica.) Fronds. A general acquaintance with the various types of fronds illustrated by recent Cycads is important to the student of fossils not only to enable him to compare existing and extinct forms but as affording safeguards against possible sources of error in the description and identification of impressions^. The verna- tion exhibits less uniformity than in Ferns: in Cycas the rachis is straight and the pinnae circinately coiled (fig. 220, B, vol. ii. p. 283); in Zamia and Stangeria the rachis is bent and the pinnae straight, while in Ceratommia and other genera both the axis and leaflets are straight. As Braun pointed out, there is as a rule no terminal leaflet, or it may be pushed to one side giving a forked appearance to the frond apex*. ' Bower (84). 2 Bo8en (11). ' Seward (95) A. pp. 15 et seq. * Braun, A. (75).. 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
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