OF THE FOSSIL PLANTS OF THE COAL-MEASTJEES. 
393 
Our history of what is known of this remarkable plant is not yet exhausted. On 
examining the fine series of coal-plants in the Liverpool Museum, which owes so much 
to the ever-vigilant energy of the Rev. H. H. Higgins, of Rainhill, I detected a series of 
cortical impressions which evidently belonged to an arborescent tree, and which I at once 
identified as having a probable relationship to my Dictyoxylons. On naming this circum- 
stance to Mr. Carruthees, he called my attention to the fact that a specimen similar 
to the Liverpool ones had been described by the late Mr. Gourlie, of Glasgow, under 
the generic name of Lyginodendron. Hr. Bryce, of Glasgow, kindly furnished me with 
Mr. Gouelie’s memoir, which at once satisfied me that the Liverpool specimens were 
varied forms of the Lyginodendron Landsburgliii of the Scotch author. Mr. Gourlie gave 
a characteristic figure of his fragment in the ‘ Proceedings of the Philosophical Society of 
Glasgow’ for February 15th, 1843, but he made no attempt to describe it scientifically, 
or to correlate it with any other known fossil plants. He obtained the fragment from the 
Rev. David Lands boro ugii, and having recognized that it was undescribed, he contented 
himself with figuring it and giving to it the above name. On turning to Corda’s ‘ Beitrage 
zur Flora der Vonvelt,’ published two years later, I found a fragment of the same kind 
figured under the name of Sagenaria fusiformis ( loc . cit. Taf. vi. fig. 4). Corda brought 
together in his plate, along with this specimen, fragments of a true Lepidodendroid 
bark, with some other plants showing internal organization ; but I am perfectly satisfied 
that fig. 4 of his plate, the Lyginodendron of Gourlie, has no relationship whatever to 
the objects associated with it. 
Plate XXVII. fig. 26, which bears the closest resemblance to Mr. Gourlie’s specimen, 
consists of a slab of sandstone whose surface is covered with oblong-fusiform elevations 
of variable dimensions ; the largest of these are fully three inches in length and nearly 
half an inch in diameter. As shown in the figure, these elevated areolations are in close 
contact with each other, being merely separated by a sharply defined groove, their 
surfaces being rounded or slightly flattened. Plate XXVII. fig. 27 represents a similar 
specimen, only in this example the largest areolie are rarely more than 2 inches in 
length and *18 in breadth; they are more uniform in size and regular in their arrange- 
ment than in fig. 26, exhibiting a greater tendency to dispose themselves in the oblique 
spiral lines of the Lepidodendroid plants than in the other specimen ; the surface 
of each areola also projects in a sharp, central, longitudinal ridge. In Plate XXVII. 
fig. 28 we have a third modification. In this example the areolae rarely exceed L5 in 
length and ‘12 in diameter, whilst they are separated from each other by flat spaces 
from *2 to '1 in breadth. Their surfaces in this instance likewise are more or less 
rounded. Plate XXVII. fig. 29 is a small specimen, also with convex areolae, which 
are very uniform in size and contour, as well as regular in their Lepidodendroid 
arrangement ; as in the last figure, flat areas intervene between the fusiform areolae. 
In a fifth specimen of this instructive series the areolae are not more than an inch in 
length, whilst in a sixth they are reduced to about half that size. Plate XXVII. fig. 28 
is a flat fragment fully 7 inches in diameter; and even the sixth example just referred to 
MDCCCLXXI1I. 3 G 
