OF LOWER GREENSAND PLANTS. 241 



similar to P. ivoburnense (p. 211), while the pitting of the tra- 

 cheids with irregularly doubled rows is like the pitting in that 

 species and in Podocarpus Schwendce. The resin-containing 

 xylem-parenchyma and the ray-cells with their smooth walls are 

 also like those of other species of the genus. The presence of 

 the peculiar specialised and stone-cells in the pith, however, is 

 distinctive, and is much more suggestive of the Podocarpaceaa than 

 of any other family. Stone-cells in the pith occur in various 

 species of the genera Araucaria, Cryptomeria, Juniperus, 

 Torrei/n, Dacri/diuni, and Podocarpus, and in a few others such 

 as isolated species of Pinus. Of these the type of pith in the 

 living Dacrydium comes nearer than the others to the fossil, 

 though in its peculiar and specialised chains of cells our new 

 fossil appears to be unique. 



V. 2117, Type-specimen. Part of a decorticated branch, now 

 about 4 cm. in diameter, of which over 20 annual 

 rings are preserved. The wood and pith are partly 

 well petrified, though the axis is riddled with teredo- 

 borings, the spaces of which are filled with a finer silt 

 with only a few coarse Greensand grains in them. 

 The stem, as a whole, is embedded entirely in the 

 coarse granular Lower Greensund matrix. The spe- 

 cimen is now 10 cm. long, and there are several 

 smaller portions of it from which sections have been 

 cut. 



V. 2117 a. Figured, PI. XXII, fig. 1. Transverse section of 

 the above, in which the plant-cells are locally very 

 beautifully preserved. The pith with its various 

 kinds of cells and the primary xylem can all be well 

 seen. 



V. 2117 b, C. Two transverse sections of the above, partly well 

 preserved, but rather thick and much fractured in the 

 mounting of the sections. 



V. 2117 d. Figured, text-fig. 67. Median longitudinal radial 

 section passing through pith, protoxylems, and secon- 

 dary wood. The wood is much eaten out by teredo- 

 borings, but is locally well preserved. The pith-cells 



