26 THE OLDEE MESOZOIC FLOEA OF VIEGINIA. 



taken from the roof-shales of the main coal, in a shaft long since filled up, 

 at a locality near Midlothian. It was preserved solely on account of the 

 beauty of the impressions found on it. Among the plants found on this 

 slab was the large fragment of Acrostichides linncecefolius depicted in Plate 

 IX, Fig. 1. To judge from the number and size of the different specimens 

 found on this slab, and the perfection of their preservation, this locality 

 must have been remarkably rich in fine impressions. The shaft from which 

 they were obtained is the "Gowry." 



All the leaf substance being preserved on this specimen from the Gowry 

 in great perfection, we are enabled to make out many details which could 

 not otherwise be observed. The portion of the frond figured was most 

 probably a primary pinna of an arborescent fern. The pinnae are extremely 

 long and slender, and are sometimes opposite. The rachis is marked 

 with two lateral ridges, one on each side, bordering a depressed channel. 

 This is also seen on Bunbury's specimen. The plant must have been a 

 very robust one, and probably was arborescent, for the specimen delin- 

 eated in Plate IX, Fig. 1, seems to be a primary pinna. The leaf sub- 

 stance of the fertile pinnae was thick and coriaceous, leaving, after being 

 compressed in the shale, a shining, granulated, and somewhat convex im- 

 pression. The pinnules are often crowded, and sometimes somewhat imbri- 

 cated. The nerves are in both the sterile and fertile pinnules slender but 

 strongly marked, and distinctly defined. In Plate IX, Fig. 1 a, I have 

 given on the magnified pinnules both the nervation and fructification of the 

 fertile portion of the plant. What the relation in position of the sterile 

 and fertile portions of the fronds to each other is I cannot say. I have 

 never seen any sterile pinnules on the fertile portion of the frond, or vice 

 versa. The pinnae were extremely long, and as a consequence their tips 

 are almost without exception wanting. In Plate VII, Fig. 3, I give a rep- 

 resentation of the only termination that I have seen. In Plate VII, Fig. 4, 

 I give a delineation of fertile pinnules that show a transition in shape ap- 

 proaching that of the sterile pinnules. 



I visited the old Gowry Shaft, now filled up, and found, after careful 

 search on the "dump," several impressions that I consider as the sterile 

 form of this plant. At first sight they do not appear to be the same species, 



