420 Proceedings of the Eoyal Physical Society. 



form of the leaf-scar and the position of the vascular cica- 

 tricules, which are central in >S^. duacensis, while those of 

 Sigillaria coriacea are placed above the centre. 



The specimens, unfortunately, do not bear any note of the 

 locality from which they were collected ; but from indirect 

 evidence there is every reason to believe that they came from 

 the Newcastle-on-Tyne Coalfield. 



The figure (PL XXI., Fig. 2) is taken from a plaster cast of 

 an impression of the plant in the British Museum. My 

 thanks are due to Dr H. Woodward, F.RS., for permission to 

 describe this species. 



Horizon. Coal-measures. 



Locality. (?) ISTewcastle-on-Tyne, Northumberland. 



3. Sigillaria Walchii, Sauveur (PL XXI., Fig. 1). 



Sigillaria WalcMi, Sauveur, Veget. foss. d. terr. liouil. de la Belgique, 

 pi. IviL, fig. 3 ;^ Boulay, Terr, houil. du uord de France et ses veget. 

 foss., p. 43. 



Description. — Ribs wide, smooth; leaf-scars separated by 

 a short interval, subtriangular, as broad as high, the upper 

 angle obtusely rounded, the lateral angles placed below the 

 centre, rounded, but distinct, the lower margin indented by a 

 slight sinus ; vascular cicatricules situated above the centre, 

 the two lateral lunate, the central punctiform. On the ribs 

 immediately above the leaf-scar is a slightly bent transverse 

 furrow. The decorticated stem is finely striated longitudi- 

 nally. 



BemarJcs. — In the specimen figured on PL XXI., Fig. 1, the 

 ribs are 20 millim. broad ; the leaf-scars, of pyriform outline, 

 are 10 millim. in height and the same in breadth ; they stand 

 about 4 millim. apart. The slightly lunate transverse furrow 

 which surmounts them is about 10 millim. long. The outer 

 surface of the bark is quite smooth. 



The elevation of the ribs is shown at Fig. Ih. They are 

 flat, but, from the perfection with which the leaf-scars are 

 preserved, I am inclined to think that the fossil has suffered 

 little from pressure. 



1 Academie royale des sciences, des lettres et des beaux-arts de Belgique, 

 1848. 



