. Fossil plants : for students of botany and geology . Paleobotany. Fig. 245. A. Marattia fraxinea. A'. A single synangium showing the two valves and pores of the sporangial compartments. B, B'. it/. Kaulfussii. C, Kaulfussia (synangium showing pores of sporangial compart- ments). D, B. Marattiopsis Milnsteri. (C, after Hooker; D, E, after Schimper.) composed of two valves, which on ripening come apart and expose two rows of pores formed by the apical dehiscence of the sporangial com- partments (fig. 245, A', B). In Marattia Kaulfussii the sori are attached to the lamina by a short stalk (fig. Stock Photo