. Fossil plants : for students of botany and geology . Paleobotany. XLVl] MORICONIA 333 at right-angles to the long axis of the pinnules (fig. 760) suggested that some at least of the vein-like markings might be the boun- daries of small scale-like leaves similar to those of Libocedrus and other Conifers. Saporta^, in his reference to the genus in an account of the Sezanne flora^ assigns Moriconia to the Cupressineae, a determination in accordance with the habit of the foliage-shoots, though in the absence of reproductive organs it is impossible to fiz its position more precisely. The characte
. Fossil plants : for students of botany and geology . Paleobotany. XLVl] MORICONIA 333 at right-angles to the long axis of the pinnules (fig. 760) suggested that some at least of the vein-like markings might be the boun- daries of small scale-like leaves similar to those of Libocedrus and other Conifers. Saporta^, in his reference to the genus in an account of the Sezanne flora^ assigns Moriconia to the Cupressineae, a determination in accordance with the habit of the foliage-shoots, though in the absence of reproductive organs it is impossible to fiz its position more precisely. The characteristic features are the pinnate branching, the flattened form of the branches, and bhe geometrically regular decussate short and broad leaves. The genus is recorded only from Lower and Middle Cretaceous rocks. Moriconia cydotoxon Debey and Bttingshausen. This, the type-species, is recorded from Cretaceous rocks at Aix-la-Chapelle, from the West coast of Greenland and the Atlantic coastal plain. Heer^ figured an imperfectly preserved specimen from Disco as Pecopteris hudlistensis in which an indication is given of the occurrence of the actual leaves, but some years later^ he de- scribed well preserved examples as Moriconia cydotoxon, and, as the result of an inspection of drawings supplied by Debey, identified them with the type-species. The same type is re- corded from the Amboy clays (fig. 760)*, Staten Island^ and Block Island. As Holhck points out, a large impression included by Heer in Moriconia cy- Moriconia should rather be referred to Brachy- clotoxon. (After New- ^%Km»i: in the arrangement of the leaves and in jj^t^^'^j^eO ° " ' the form of the short and blunt lateral foliage- shoots Moriconia agrees closely with some examples of Brachy- phyllum crassum^ in which the leaves appear to be regularly de- cussate. The leaves of Moriconia are wholly appressed and the upper edge of the lamina is rounded and almost truncate; a mMian Une, possibly due to the pres
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Keywords: ., bookcentury1800, bookdecade1890, bookpublishercambr, bookyear1898
