58 DESCRIPTION OF FOSSIL TREES DISCOVERED 



rangement, and presents marks of two branches or twigs. The exterior 

 is irregularly and longitudinally striated, and was covered by a layer of 

 coaly matter. The interior is intersected by veins of clayey matter and 

 calcareous spar. Some of the concentric layers are partially separated 

 and dislocated by the intrusion of similar substances. The colour is dull 

 brown, but a slice viewed by transmitted light is bright umber. This 

 figure is of the natural size. It represents the central pith, the numerous 

 layers of woody tissue, the interjected foreign matter irregularly tortuous, 

 or extending between the layers, and the white divergent veins of calcare- 

 ous spar. 



Fig. 2. A portion of a transverse slice magnified about fifty-five times, 

 shewing the ordinary appearance of the interior. Two of the limits of the 

 concentric layers are seen, being filled with earthy and carbonaceous mat- 

 ter, which has in like manner been interposed in the direction of the medul- 

 lary rays. The structure is still more distinctly seen in the next figure. 



Fig. 3. A portion of a transverse slice of the same fossil, magnified 

 about forty-five times. On comparing this and Fig. 2, with the figures re- 

 presenting portions of Coniferae in Plates I. and II., it will be seen that the 

 tissue is perfectly similar, consisting of regular series of four-sided or sub- 

 hexagonal meshes, with medullary rays intervening, the apertures of the 

 cellules nearest the outer limit of each annual layer being more or less ob- 

 structed. We have hitherto seen nothing so perfectly resembling the tis- 

 sue of our recent pines. 



Fig. 4. Represents a portion of the same enlarged in the same degree, 

 exhibiting the texture in its most delicate form. 



Fig. 5. This represents the central part or pith, enlarged in the same de- 

 gree, together with part of the first woody layer, containing medullary rays. 

 I can find no traces of vessels. While we wonder that so delicate and 

 regular a texture should have survived the lapse of ages, and the ruin of 

 worlds, we cannot but feel gratified in being enabled to trace so intimate a 

 resemblance between plants belonging to epochs so remote from each other. 



There now remains to be determined the structure of the walls of the 

 elongated cellules, but as I have examined and caused to be figured several 



