a 
PLATE 68. 
Fig. 1. 
314. 1. Sphenothallus angustifolius. 
(Pag. 261.) 
Fig. 2. 
315. 2. Sphenothalltjs latifolius. 
(Pag. 262.) 
2 a. A leaf 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. 
316. 4. Buthotrephis subnodosa. 
(Pag. 262.) 
Fig. 3. 
3 a, b. Figures of imperfect specimens, illustrating the prevailing form of the species. 
