60 ROYAL SOCIETY OF CANADA 



tened fragment of a stem or branch without the leaves, may thus be 

 placed either with the scars on the upper or lower angle of the leaf-base, 

 and they have been figured by authors in bothtpositions. The former is 

 the position when young, the latter when old. In^the former condition 

 the plant may be referred to Lepidodendron, or to Lomatophloios of Corda. 

 In the latter it is the adult condition of Lepidophloios. This will appear 

 more clearly in describing the species in detail. (See Plate IV.) 



Fig. a.— Young and old leaf-bases of Lepidophloios enlarged. 



(2) Internal Structure. 



Only one specimen of the species L. Acadianus has afforded to me 

 fairly well preserved internal structure. It was figured and described in 

 my paper of 1865, and some addkional preparations have since been 

 made, and have been micro-photographed through the kindness of Prof 

 Penhallow, of McGill University. (Plate YI.) 



The specimen is a portion about two feet in length, apparently of a 

 large branch, with two rows of cone-scars, and is slightly flattened, its 

 longest diameter being about 4^ inches. It is mineralised with clay- 

 ironstone, calcite and pyrite, and was obtained from the workings of the 

 Albion Colliery in Pictou, Nova Scotia. The woody axis is scarcely an 

 inch in diameter, and only its outer portion has the structure preseiwed, 

 while outside of this a large portion of the stem, probably occupied by 

 perishable parenchyma, has disappeared. External to the last is a ring 

 of fine-grained quadrangular and imperfectly radiating tissue, about a 

 quarter of an inch in thickness, and probably corresponding to what has 



