PLATE XV. 



Fig. 1 — 4. Rachises of ferns (or pteridosperms). 



— 5, 6. Calymmatotheca bifida L. & H. sp. 



— 7 — 10. Asterocalamites scrobiciilatus Schloth. sp. 7, fragment 



of the stem with 3 nodes (at a, b and c); 8, part of 

 the node at c, magnified; 9 part of the surface of an- 

 other fragment with the "swollen" ribs at the node ; 

 10, the same as fig. 9 magnified. 



— 11 — 22. Sphenophijlhim tenerrimiim Ett. sp. var. elongatiim D. 



White. 11 — 16, fragments of stems; 17, 18, stem-frag- 

 ments with remains of leaves at the nodes; 19, the 

 same as fig. 18, magnified; 20, part of a verticil; 21, 

 two verticils still adhering to the stem; 22, one of the 

 leaves of fig. 21 magnified. 

 23. Sfigmaria ficoides Sternb. sp. Fragment. 



