14 ARKIV FÖR BOTANIK. BAND if. NIO 1. 



advisable not to undertake this change of nomenclature at 

 present. Zeiller's account of the sporangia of Cladophlebis 

 (Todea) Roesserti (Presl) Sap. would seem to show that 

 there is in this case a closer resemblance to the osmundaceous 

 type than in the English material of Todites examined by 

 Thomas. (Zeeller 1903, p. 38 and foil.) As the fertile spe- 

 cimens figured by Zeiller undoubtedly are of the Todites 

 type, as usually conceived, matters do not yet seem to be quite 

 clear, and the name Cladotheca has therefore been provisionally 

 retained. 



In pi. 2, figs. 9 — 12, some sporangia of Cladotheca undans 

 are shown. They are from the same specimen as those figured 

 in pi, 1 of my previous paper: those in the present pi. 2, figs. 

 9, 10, and 12 were also figured before. These new illustrations 

 are published because it has now become possible, by means 

 improved methods, to obtain somewhat better photographs of 

 these objects, which are not very suitable for photographic 

 reproduction. The figures are intended to show the apical 

 cap of thick-walled cells and the radial symmetry of the spor- 

 angia, which offers a strong contrast to the dorsiventral struc- 

 tm'e of the osmundaceous sporangium. 



This type of sporangia has been found to occur in yet 

 another species, viz. Asplenites cladophleboides Möller from 

 the Liassic of Bornholm. In the type specimen figured by 

 Möller (1902, p. 27; pi. 2, fig. 20) only a comparatively'' 

 small number of sporangia is preserved; but these show the 

 characteristic apical cap of thickened cells with sufficient 

 distinctness. The type specimen of Möller agrees very 

 closely with Cladotheca undans and should probably be re- 

 ferred to that species. 



Dictyophylliim Lindl. & Hltt. 

 Dictyophyllum exile (Brauns) Nath. (PI. 2, figs. 13—16.) 



Of the different species of Dictyophyllum, the Rhaetic 

 species D. exile (Brauns) Nath. seems to afford the best 

 material for a study of the sporangia. Especially the ma- 

 terial described by Nathorst (1906) displays the sporangia 

 with unusual distinctness. 



Though several species of Dictyophyllum have been de- 



