PLATE 68. 



Fig. 1. 314. 1. Sphenothallus angtjstifoliits, (Pag. 261.) 



Fig. 2. 315. 2. Sphenothallus latifolius. (Pag. 262.) 



a a. A leal' nearly entire, showing a depressed line along the centre. 



2 b. A similar leaf, with a sharp ridge along the centre. 



2 c. A leaf of a narrower and more elongated form, with a broad ridge along the centre. 



2 d. Another fragment, with a ridge extending a part of the length. 



2 e,f. Fragments of what may have been stems of this plant. 



Fig. 3. 316. 4. BuTHOTREPHis suBNODosA. (Pag- 262.) 



3 u, b. Figures of imperfect specimens, illustrating the prevailing form of the species. 



