. Fossil plants : for students of botany and geology . Paleobotany. XXXV] SAMAROPSIS 337 wings. It is advisable to restrict the designation Samaropsis to Palaeozoic seeds. Nucules deprived of the broad border would be referred to Cordaicarpus as usually employed for impressions. The generic name Samaropsis serves a useful purpose as a distinc- tive term for platyspermic seeds preserved as casts or impressions characterised by the possession of a wide border or wing broader than in typical examples of Cordaicarpus. The specimen represented in fig. 499 affords a good illustration of the differen
. Fossil plants : for students of botany and geology . Paleobotany. XXXV] SAMAROPSIS 337 wings. It is advisable to restrict the designation Samaropsis to Palaeozoic seeds. Nucules deprived of the broad border would be referred to Cordaicarpus as usually employed for impressions. The generic name Samaropsis serves a useful purpose as a distinc- tive term for platyspermic seeds preserved as casts or impressions characterised by the possession of a wide border or wing broader than in typical examples of Cordaicarpus. The specimen represented in fig. 499 affords a good illustration of the difference between Samaropsis and Cordaicarpus. In this specimen the border clearly consists of two portions, an inner narrower border (black in the drawing) and an outer more dehcate portion; the former is the impression of the sclerotesta and the outer represents the fleshy j,^^ ^gg ~~^^ ^ ^ sarcotesta which in the hving seed may have emarginata, from the formed a wing. If, as often happens, the Westphalian series, seed were preserved with the narrow border „°jj ^^ '^ ^ °° only it would be assigned to Cordaicarpus, many species of which are undoubtedly incomplete Samaropsis seeds. The seeds described by Lindley and Hutton as Cardiocarpon aculum (fig. 444, p. 171) have been made by Arber^ the type of a new genus Cornucarpus, the distinguishing feature being the triangular form and the apical horns of the wing. The seeds figured by Arber^ from the Kent coalfield as Cornucarpus acubus are, however, not identical with the type of Lindley and Hutton, which has the characters of Samaropsis. Samaropsis is widely distributed in Permo-Carboniferous rocks in Europe and North America and is recorded also from India* (fig. 504), China*, South Africa5 (fig. 503), South America* (fig. 502, F, G) and AustraUa''. Some seeds of this form were certainly borne on Cordaitean plants (cf fig. 480, A), but seeds of similar type have been found in organic connexion with the foHage of Pteridosperms (fig
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