Geological magazine . Pterophtlltjm sp. (PI. V, Figs. 2 and 4.) The other new plant, which is of nearly equal interest, is repre-sented by some fragments of leaves, which appear to belong to thegenus Pterophyllum. They were obtained from the same boring atBarfreston, at a depth of 1,834 feet, in the Transition Coal-measures. The two specimens figured on PL V, Figs. 2 and 4, show a some-what stout rachis with fragments of pinnules still attached. Noneof the latter, however, are complete. The longest leaflet, slightlyexceeding 1 cm. in length, is seen at the top of Fig. 2, which isenlarged nearl
Geological magazine . Pterophtlltjm sp. (PI. V, Figs. 2 and 4.) The other new plant, which is of nearly equal interest, is repre-sented by some fragments of leaves, which appear to belong to thegenus Pterophyllum. They were obtained from the same boring atBarfreston, at a depth of 1,834 feet, in the Transition Coal-measures. The two specimens figured on PL V, Figs. 2 and 4, show a some-what stout rachis with fragments of pinnules still attached. Noneof the latter, however, are complete. The longest leaflet, slightlyexceeding 1 cm. in length, is seen at the top of Fig. 2, which isenlarged nearly twice. The leaflets are fairly distant from one another,from 1 to 15 mm. broad, and appear to be slightly contracted at thebase. Each has three or more parallel nerves, which fork occasionallynear the base. These are seen on Fig. 4, which is three times enlarged. There appears to be little doubt that these leaves are of Cycado-phytean affinity. I have shown them to Professor Nathorst and Geol. Ma(;. 191-2. Plate W. Tains photo. Dictijocalamites and PteropJujllum from the Kent Coal-field. E. A. Neu-ell Arber—Plants from Kent Coal-field. 99 other palseobotanists, and they agree with me in this believe them to be members of the genus Pterophyllum, one of theearliest types of leaf belonging to members of this alliance, appearingfirst of all in Carboniferous times. They may be compared withPterophyllum hlechnoides, from the Stephanian of the Black!Forest. Other species of this genus are known from the Stephanianand Permian of other parts of Germany, and especially from of this type are also abundant in the earlier Mesozoic rocks. The occurrence of a Pterophyllum, even although the fionds are toofragmentaiy to warrant specific determination, in beds containinga typical Transition Coal-measure flora, is a quite unique experiencein England, and, so far as I am aware, in the Westphalian rocks ofEurope. Such rare cases illustrate the first slow
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Keywords: ., bookcentury1800, bookdecade1860, booksubjectgeology, bookyear1864
