ANNIVERSARY ADDRESS OF THE PRESIDENT. 177 



shale, like underclay, but no Stigmarioe visible, spring several upright Ca- 

 lamites, three of them in the distance of two feet, and eight more, the 

 whole eleven in the distance of twenty feet." 



6. The next, 137 feet lower, in sandstone, are upright Calamites, three 

 in the space of a foot. 



t. From a carbonaceous shale, a foot thick, sixty- two feet lower, " spring 

 up erect Calamites, penetrating an arenaceous shale above two feet ; and 

 there are seven in the space of eight feet." 



K. The next is 254 feet lower, where, from an argillaceous shale, springs 

 an upright Sigillaria, four inches in diameter ; five feet of it are seen in a 

 sandstone above. Argillaceous and carbonaceous shale beneath, six feet 

 thick, does not contain Stigmarice. 



A. From a grey argillaceous shale, twenty-two feet lower down, springs 

 an upright Sigillaria. Its roots spread out into the shale, which is ten 

 feet thick, and does not contain Stigmarics ; but over it lies a grey, crumbly, 

 argillo-arenaceous shale or sandstone with Stigmarice, in which six feet of 

 the stem are visible. From the root of the plant proceeds a Stigmaria 

 branch, which at first sight had much the appearance of being a root of 

 the Sigillaria, but close inspection showed that the two, although touching^ 

 were distinct. 



(4.. The next is 108 feet lower, where, from a grey argillaceous shale, 

 " springs an upright Sigillaria, eighteen inches in diameter, penetrating an 

 incumbent sandstone." Fourteen feet of argillaceous shale and sandstone 

 beneath do not contain Stigmarioe. 



V. The next is 133 feet lower, where, from a thin seam of coal with 

 carbonaceous shale beneath, *' rises d.xiVi'^n^X. Sigillaria \ the roots spread 

 on the top of the coal ; the plant is a foot in diameter, and only one foot 

 of the length is visible." 



|. The next is 160 feet lower, where, from a red argillaceous shale, 

 springs an upright Sigillaria. Two feet of the length is seen, but it is cut 

 clean off at the top and at the bottom by the measures which pass both 

 without disturbance. No Stigmarice occur for many yards below. 



0. The next is 101 feet lower, where, from grey argillaceous shale, six 

 feet thick, without Stigmarice, starts an upright Sigillaria, four inches in 

 diameter ; it is planted two feet in the shale, and penetrates the sandstone 

 above, being four feet in length altogether. 



^. The next is 362 feet lower, where, from a red and dark grey varie- 

 gated shale, twenty-eight feet thick, with small balls of ironstone and Stig- 

 marice, arise two upright Sigillarice. The roots of these spread out just 

 on the top of the bed, and two feet of the plant are visible. The roots of 

 the other spread out likewise, but they sink deeper into the shale by two 

 feet, and the plant penetrates farther into the superincumbent sandstone." 



^. The next distinct instance is 490 feet lower, where, from a grey ar- 

 gillaceous shale, several upright Calamites from half an inch to four inches 

 in diameter penetrate an incumbent grey arenaceous and argillaceous shale 

 containing prostrate carbonized plants. The roots of a Calamite three 

 inches in diameter, spread on the top of the shale underneath ; and twenty- 

 one more Calamites are visible along the bank in the space of twenty 

 yards. 



This is the last instance stated of stems of plants found in the 

 strata perpendicular to the plane of stratification ; the seventeen in- 

 stances thus occurring in a vertical thickness of 4515 feet. 



Throughout the whole 7000 feet in the South Wales section, and, 

 if the limestones are, as is most probable, of freshwater origin, also 



VOL. II. — PART I. N 



