OF LOWER, GltEENSANU PLANTS. 



263 



(cf. PI. XXVIII, fig. 2). Between these, and also towards the 

 ends of many of the vessels, the bordered pits are intermingled 

 with and give place to broad, regular, scalariform perforations 

 (PI. XXVII, fig. 2). The minute dots in the smaller pits, 

 which can be just made out in the photograph (PI. XXVII, 

 fig. 1 6), appear to be due to mineral granules caught on the pit 

 borders, so that their appearance of being " sieve-like areas," 

 such as are described in the vessels of a number of the higher 

 Dicotyledons by Jousson, 1892, is deceptive. 



Text-fig. 77. Caiifia arborescens, sp. nov. Radial longitudinal section 

 showing the vessels, v., and tbeir pitting ; the tibre-tracheids, p. ; and 

 the medullary rays, *., in which the end-walls, a., are much thickened 

 and pitted, and the radial walls have groups of large round pits, r. 

 The terminal cells, e., of the ray are slightly larger and squarer 

 than the others. X 400. No. V. 13231 c. 



Nearly all the vessels show the end- walls of numerous iyloses 

 (PI. XXVIII, fig. 1, t.}. 



The wood-fibres or fibre-traclieids are inconspicuous in trans- 

 verse section. They are roughly oblong or hexagonal in 

 transverse section, according to the space in which they have 



r 



