280 DESCRIPTIVE CATALOGUE 



have been very soft in texture. The vessels arc fairly large, and 

 are numerous, scattered chiefly singly but often in lateral pairs. 

 Between them are small groups of thin-walled elements, ap- 

 p irently parenchyma, and a small number of wood-fibres with 

 but slightly thickened walls. Owing to the presence of numerous 

 fungal hyph, and to a rather curious type of petrifaction, there 

 is reason to believe that the apparent delicacy of all the walls 

 may be to some extent petrifact. 



Grou'tli-rmys, if they were present, must have been rather 

 wide, but they are obliterated by the excessive crushing of all 

 tho tissues prior to petrifaction. 



.M c(hill it, -if rmjs are very numerous, apparently nearly all 

 niiiftiseriate with a large number of cells composing them, a 

 do/.en cells or more composing an average ray. The cells appear 

 to be of at least two kinds, the majority being very much elon- 

 gated radially and extremely narrow ; the rays are bordered in 

 many cases by oval shorter cells. So far as I can judge, all the 

 narrow cells appear to be thin-walled, but evidence on this point 

 is obscure. The rays are very high, rays up to 150 cells in 

 vertical series and more being frequent. 



DETAILS OF THE ELEMENTS. The wood-vessels are now rather 

 crumpled in most cases, but appear to have been roughly circular 

 when alive. They average about 50-70 p in diameter. The 

 walls are now extremely slender, with barely any sign of 

 lignification in transverse sections. In longitudinal section the 

 pittings can be seen in many places (PI. XXX, fig. 3). The pits 

 are round, oval, or much elongated, so that they merge into a 

 sealariform type here and there anywhere along the length of 

 the vessel. These sealariform pittings are quite distinct from 

 those well-marked scalariforra end-walls found in so many 

 species. Tyloses are to be seen in nearly all cases, filling the 

 vessels. 



The wood-fibres are inconspicuous, and have but slightly 

 thickened walls. They are oval, hexagonal, or variously shaped, 

 according to space demands, and have small intercellular spaces 

 at their corners. They vary considerably, averaging roughly 

 8-20 ^i in diameter. I am uncertain as to the nature of their 

 pitting ; a few seem to have roundish, slightly bordered pits. 



Wood-parencliijma appears to be scattered in considerable 

 quantities in the transverse sections, sometimes adjacent to the 

 vessels. 



