Stewartiopteris sp. 1 and sp. 2

(Fig. 7C, D)

The large rachis (Fig. 7C), shows a broad C-shaped xylem strand (arrows, Fig. 7C) and outer sclerenchymatous cortex; it represents the proximal region of a frond. The smaller rachis shown on Figure 7D is quite distinct in cortical organization. It certainly corresponds to a second order rachis alongside the corresponding third order rachis (R3, Fig.7D) which is in connection with a fertile pinnule (P, Fig. 7D). These two Stewartiopteris rachises certainly belonged to different fronds.

Foliage of these tree ferns occasionally occurs as dense accumulations of vegetative and/or fertile pinnules as shown on Figure 7E. One section of an ultimate pinna, paradermal to the pinnule surfaces (Fig. 7F), reveals their pecopteroid morphology. At least three different taxa occur in the assemblage as is suggested by differences in the fertile pinnae.